0001039684 srt:NonGuarantorSubsidiariesMember srt:ReportableLegalEntitiesMember 2018-01-01 2018-12-31


UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 10-K
FORM 10-K

XANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 20162019.
OR
__ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from __________ to __________.

Commission file number  001-13643
okelogo.jpg
ONEOK, Inc.
(Exact name of registrant as specified in its charter)
Oklahoma73-1520922
(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer Identification No.)
 
100 West Fifth Street,Tulsa,OK74103
(Address of principal executive offices)(Zip Code)
Registrant’s telephone number, including area code   (918) (918) 588-7000
Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
Common stock, par value of $0.01OKENew York Stock Exchange
(Title of each class)(Name of each exchange on which registered)
Securities registered pursuant to Section 12(g) of the Act:  None
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. YesX No__No .

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes __  NoX.

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.  YesX  No __

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every
Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).  YesX No __

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Registration S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. __
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”filer,” “smaller reporting company” and “smaller reporting“emerging growth company” in Rule 12b-2 of the Exchange Act.  (Check one)
Large accelerated filerX    Accelerated filer __    Non-accelerated filer __    Smaller reporting company __
Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes__Yes No X.

Aggregate market value of registrant’s common stock held by non-affiliates based on the closing trade price on June 30, 2016,28, 2019, was $9.7$28.1 billion.

On February 21, 2017,18, 2020, the Company had 210,757,806413,319,000 shares of common stock outstanding.
DOCUMENTS INCORPORATED BY REFERENCE:
Portions of the definitive proxy statement to be delivered to shareholders in connection with the Annual Meeting of Shareholders to be held May 24, 2017,20, 2020, are incorporated by reference in Part III.



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ONEOK, Inc.
20162019 ANNUAL REPORT

  Page No.
 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
   
 
 
 
 
 
   
 
 
  


As used in this Annual Report, references to “we,” “our”“our,” or “us” refer to ONEOK, Inc., an Oklahoma corporation, and its predecessors and subsidiaries including ONEOK Partners and its subsidiaries, unless the context indicates otherwise.

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GLOSSARY


The abbreviations, acronyms and industry terminology used in this Annual Report are defined as follows:
$1.5 Billion Term Loan AgreementThe senior unsecured delayed-draw three-year $1.5 billion term loan agreement dated November 19, 2018
$2.5 Billion Credit AgreementONEOK’s $2.5 billion revolving credit agreement, as amended
AFUDCAllowance for funds used during construction
Annual ReportAnnual Report on Form 10-K for the year ended December 31, 20162019
ASUAccounting Standards Update
BblBarrels, 1 barrel is equivalent to 42 United States gallons
BBtu/dBillion British thermal units per day
BcfBillion cubic feet
Bcf/dBillion cubic feet per day
BtuBritish thermal unit
CFTCU.S. Commodity Futures Trading Commission
Clean Air ActFederal Clean Air Act, as amended
Clean Water ActFederal Water Pollution Control Act Amendments of 1972, as amended
DJDenver-Julesburg
DOTUnited States Department of Transportation
EBITDAEarnings before interest expense, income taxes, depreciation and amortization
EPAUnited States Environmental Protection Agency
Exchange ActSecurities Exchange Act of 1934, as amended
FERCFederal Energy Regulatory Commission
FoundationONEOK Foundation, Inc.
GAAPAccounting principles generally accepted in the United States of America
GHGGreenhouse gas
Intermediate Partnership
ONEOK Partners Intermediate Limited Partnership, a wholly owned subsidiary of
ONEOK Partners, L.P.
IRSInternal Revenue Service
KCCKansas Corporation Commission
LIBORLondon Interbank Offered Rate
MBblThousand barrels
MBbl/dThousand barrels per day
MDth/dThousand dekatherms per day
Merger Agreement
Agreement and Plan of Merger, dated as of January 31, 2017, by and among
ONEOK, Merger Sub, ONEOK Partners and ONEOK Partners GP
Merger SubNew Holdings Subsidiary, LLC, a wholly owned subsidiary of ONEOK
Merger Transaction
The transaction, contemplated by the Merger Agreement pursuant toeffective June 30, 2017, in which
ONEOK will acquireacquired all of ONEOK Partners’ outstanding common units
representing limited partner interests in ONEOK Partners not already directly
or indirectly owned by ONEOK
MMBblMillion barrels
MMBbl/dMillion barrels per day
MMBtuMillion British thermal units
MMcf/dMillion cubic feet per day
Moody’sMoody’s Investors Service, Inc.
Natural Gas ActNatural Gas Act of 1938, as amended
Natural Gas Policy ActNatural Gas Policy Act of 1978, as amended
NGL(s)Natural gas liquid(s)
NGL products
Marketable natural gas liquid purity products, such as ethane, ethane/propane
mix, propane, iso-butane, normal butane and natural gasoline
Northern Border PipelineNorthern Border Pipeline Company, a 50% owned joint venture
NYMEXNew York Mercantile Exchange
NYSENew York Stock Exchange
OCCOklahoma Corporation Commission
ONE GasONE Gas, Inc.
ONEOKONEOK, Inc.
ONEOK Credit Agreement
ONEOK’s $300 million amended and restated revolving credit agreement
effective as of January 31, 2014
ONEOK PartnersONEOK Partners, L.P.
ONEOK Partners CreditTerm Loan Agreement
ONEOK Partners’ $2.4The senior unsecured three-year $1.0 billion amended and restated revolving credit
term loan agreement effective as ofdated January 31, 2014,8, 2016, as amended
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ONEOK Partners GP
ONEOK Partners GP, L.L.C., a wholly owned subsidiary of ONEOK and the sole
general partner of ONEOK Partners
OPISOil Price Information Service
OSHAOverland Pass PipelineOccupational Safety and Health Administration
Partnership Agreement
Third Amended and Restated Agreement of Limited Partnership of ONEOK
Partners, L.P., as amended
Overland Pass Pipeline Company, LLC, a 50% owned joint venture
PHMSA
United States Department of Transportation Pipeline and Hazardous Materials
Safety Administration
POPPercent of Proceeds
Quarterly Report(s)Quarterly Report(s) on Form 10-Q
RoadrunnerRoadrunner Gas Transmission, LLC, a ONEOK Partners 50 percent50% owned joint venture
RRCRailroad Commission of Texas
S&PS&P Global Ratings
SCOOPSouth Central Oklahoma Oil Province, an area in the Anadarko Basin in Oklahoma
SECSecurities and Exchange Commission
Securities ActSecurities Act of 1933, as amended
Series E Preferred StockSeries E Non-Voting, Perpetual Preferred Stock, par value $0.01 per share
STACKSooner Trend Anadarko Canadian Kingfisher, an area in the Anadarko Basin in Oklahoma
Term Loan AgreementTax Cuts and Jobs ActONEOK Partners’ senior unsecured delayed-draw three-year $1.0 billion term loan agreement dated January 8, 2016H.R. 1, the tax reform bill, signed into law on December 22, 2017
Topic 606Accounting Standards Update 2014-09, “Revenue from Contracts with Customers”
West Texas LPGWest Texas LPG Pipeline Limited Partnershippipeline and Mesquite Pipelinepipeline
WTIWest Texas Intermediate
WTLPGWest Texas LPG Pipeline Limited Partnership
XBRLeXtensible Business Reporting Language


The statements in this Annual Report that are not historical information, including statements concerning plans and objectives of management for future operations, economic performance or related assumptions, are forward-looking statements. Forward-looking statements may include words such as “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “project,“forecast,” “goal,” “guidance,” “intend,” “may,” “might,” “outlook,” “plan,” “believe,“potential,” “project,” “scheduled,” “should,” “goal,“will,“forecast,” “guidance,” “could,” “may,” “continue,” “might,” “potential,” “scheduled”“would” and other words and terms of similar meaning. Although we believe that our expectations regarding future events are based on reasonable assumptions, we can give no assurance that such expectations andor assumptions will be achieved. Important factors that could cause actual results to differ materially from those in the forward-looking statements are described under Part I, Item 1A, “RiskRisk Factors, and Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations and “Forward-Looking Statements,” in this Annual Report.

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PART I


ITEM 1.    BUSINESS


GENERAL


We are a corporation incorporated under the laws of the state of Oklahoma, and our common stock is listed on the NYSE under the trading symbol “OKE.” We are the sole general partnera leading midstream service provider and as of December 31, 2016, owned 41.2 percent of ONEOK Partners (NYSE: OKS),own one of the largest publicly traded master limited partnerships. Our goal is to provide managementnation’s premier NGL systems, connecting NGL supply in the Rocky Mountain, Permian and resources to ONEOK Partners, enabling it to execute its growth strategiesMid-Continent regions with key market centers and allowing us to growan extensive network of natural gas gathering, processing, storage and transportation assets. We apply our dividend. ONEOK Partners applies its core capabilities of gathering, processing, fractionating, transporting, storing and marketing natural gas and NGLs through the rebundling of servicesvertical integration across the midstream value chains through vertical integration in an effortchain to provide itsour customers with premium services at lower costs. ONEOK Partners is a leader in the gathering, processing, storagewhile generating consistent and transportation of natural gas in the United States. In addition, ONEOK Partners owns one of the nation’s premier natural gas liquids systems, connecting NGL supply in the Mid-Continent, Permian and Rocky Mountain regions with key market centers.sustainable earnings growth.

Midstream Value Chain
Legend
valuechaingraphic6a01.gif
We are connected to supply in natural gas and NGL producing basins and have significant basin diversification, including the Williston, Permian, Powder River and DJ Basins and the STACK and SCOOP areas. In our Natural Gas Gathering and Processing segment, we have more than 3 million dedicated acres in the Williston Basin and approximately 300,000 dedicated acres in the STACK and SCOOP areas. In our Natural Gas Liquids segment, we are the largest NGL takeaway provider in the Williston Basin; Oklahoma, including the STACK and SCOOP areas; Kansas; and the Texas Panhandle. We also have a significant presence in the Permian Basin.

Natural Gas Gathering & Processing
Natural Gas Liquids
Natural Gas Pipelines
Raw natural gas is typically gathered at the wellhead, compressed and transported through pipelines to our processing facilities. Most raw natural gas produced at the wellhead contains a mixture of NGL components, such as ethane, propane, iso-butane, normal butane and natural gasoline, which remain in a mixed unfractionated form.
Once processed, residue natural gas is recompressed and delivered to intrastate and interstate natural gas pipelines.
Gathered wellhead natural gas is directed to our processing plants to remove NGLs, resulting in residue natural gas (primarily methane).
valuechain2graphic3.gif
NGLs extracted at processing plants, both third-party and our own, are then gathered by our NGL gathering pipelines.
Gathered NGLs are directed to our downstream fractionators in the Mid-Continent region and Mont Belvieu, Texas, to be separated into purity products.
Residue natural gas is transported to storage facilities and end-users, such as large industrial customers, natural gas and electric utilities serving commercial and residential consumers, and international markets through liquefied natural gas exports.

Purity products are stored or distributed to our customers, such as petrochemical companies, propane distributors, heating fuel users, ethanol producers, refineries and exporters.

EXECUTIVE SUMMARY


On January 31, 2017, weBusiness Update and ONEOK Partners entered into the Merger Agreement, by and among ONEOK, Merger Sub, ONEOK Partners and ONEOK Partners GP, the general partner of ONEOK Partners, pursuant to which we will acquire all of the outstanding common units representing limited partner interests in ONEOK Partners not already directly or indirectly owned by us. Upon the terms and conditions set forth in the Merger Agreement, Merger Sub will be merged with and into ONEOK Partners, with ONEOK Partners continuing as a wholly owned subsidiary of ours, in a taxable transaction to ONEOK Partners’ unitholders. For additional information on this transaction, see Note B of the Notes to Consolidated Financial Statements in this Annual Report.

ONEOK Partners operates predominantlyMarket Conditions - We operate primarily fee-based businesses in each of itsour three reportable segments, and itsour consolidated earnings were approximately 88 percent90% fee-based in 2016. We continue to expect demand for ONEOK Partners’ midstream services to provide supply and market connectivity. We expect producers to require midstream services to connect production with end-use markets,2019. Volumes increased demand for NGL products from the petrochemical industry and NGL exporters and increased demand for natural gas from power plants currently fueled by coal and natural gas exports to Mexico. While theacross our system in our Natural Gas Gathering and Processing and Natural Gas Liquids segments generate predominately fee-based earnings, those segments’ resultsin 2019, compared with 2018, as a result of operations are exposedour completed capital-growth projects, continued drilling and producer improvements in production due to volumetric risk. ONEOK Partners’ exposureenhanced completion techniques, offset partially by natural production declines. Since the beginning of 2018, we have completed several capital-growth projects that include NGL pipelines, NGL fractionators, natural gas processing plants and related natural gas and NGL infrastructure, and expect capital expenditures to volumetric risk can result from reduced drilling activity, severe weather disruptions, operational outagesdecrease in 2020 and ethane rejection.
ONEOK Partners has available capacity on its integrated network of assets2021, compared with 2019. Our NGL projects in the Gulf Coast allow flexibility to grow fee-based earnings with minimal capital investment.add NGL fractionators, NGL storage and, potentially, new export facilities in the future. We expect eachthese projects to meet the needs of producers, natural gas processors and the three business segmentspetrochemical industry that require additional midstream infrastructure to benefit fromaccommodate increasing producer activitysupply and demand.

We experienced fluctuating NGL location price differentials due to increased supply, increased demand in the Mid-Continent region, from the highly productive STACKinfrastructure constraints and SCOOP areas, where there was an increase in producer activity in late 2016, which we expect to continue in 2017. ONEOK Partners has a strong presenceslower demand growth in the Mid-Continent region,Gulf Coast due primarily to delays in the startup of petrochemical facilities and constrained NGL export facilities. The Conway-to-Mont Belvieu OPIS price differential for ethane in ethane/propane mix averaged $0.07 per gallon in 2019, compared with the$0.15 per gallon in 2018, which resulted in lower earnings from our optimization and marketing activities in our Natural Gas Liquids segment’s gathering system serving as a primarysegment. We expect narrower NGL takeaway provider through connectionslocation price differentials in 2020.

Rocky Mountain Region - We expect to more than 100 third-party natural gas processing plants,benefit from increased production in this region, which includes the Natural Gas GatheringWilliston, Powder River and Processing segment’s substantial acreage dedications in some of the most productive areas and the Natural Gas Pipelines segment’s broad footprint.DJ Basins. In theour Natural Gas Gathering and Processing segment, ONEOK Partners has approximatelygathered and processed volumes increased in 2019, compared with 2018, due primarily to our capital-growth projects, new well connections and increased producer productivity. Our Demicks Lake I natural gas processing plant was placed in service in October 2019, and we expect it to reach its 200 MMcf/d capacity in the first quarter 2020 due to natural gas flaring by producers on our more than 3 million dedicated acres in the Williston Basin. In addition, we completed construction of our Demicks Lake II natural gas processing plant in January 2020. With continued volume growth expected, we are in the process of expanding our Bear Creek plant by 200 MMcf/d, which is expected to be completed in first quarter 2021, and recently announced plans to construct our Demicks Lake III natural gas processing plant, with capacity of 200 MMcf/d and 100 MMcf/dexpected completion in the third quarter 2021. Upon completion of availablethese projects, our total processing capacity will be approximately 1.9 Bcf/d in the Williston Basin and Oklahoma, respectively. Asis expected to help producers continuemeet North Dakota’s natural gas capture targets and add incremental NGLs to developour NGL gathering system.

In our Natural Gas Liquids segment, we announced the completion of our Elk Creek pipeline in December 2019. We are the largest NGL takeaway provider and expect our NGL pipelines to transport more than 240 MBbl/d of NGLs out of this region by the end of the first quarter 2020 due to a combination of growth in volumes from our new and existing processing plants, third-party processing plants and volumes previously transported by rail. In addition, we recently announced an expansion of our Elk Creek pipeline to 400 MBbl/d by adding additional pump stations. The project is expected to be fully completed in the third quarter 2021, with a portion of this incremental capacity available as early as first quarter 2021. In April 2019, we announced a project to extend our Bakken NGL pipeline into an area of the Williston Basin with limited access to NGL pipeline takeaway capacity. This project will provide connectivity for third-party processing plants to key NGL market centers as well as provide additional volumes to our Elk Creek pipeline. To accommodate expected volumes, we are also expanding our Mid-Continent NGL fractionation facilities by 65 MBbl/d and constructing an extension of our Arbuckle II pipeline farther north.

Mid-Continent Region - In our Natural Gas Liquids segment, we are the largest NGL takeaway provider in the STACK and SCOOP areas we expect natural gas and NGLwhere volumes continued to increase in 2017,2019, compared with 2016 volumes, and increased2018. We expect continued demand for ONEOK Partners’our services from producers that need incremental takeaway capacity for natural gas and NGLs out of thethis region.

The In our Natural Gas Gathering and Processing segment’s earnings were approximately 80 percent fee-basedsegment, natural gas gathered and processed volumes increased in 2016. Fee revenues averaged 76 cents per MMBtu,this region in 2019, compared with an average of 44 cents per MMBtu2018, due primarily to new well connections. We expect volumes in 2015 duethis region to restructuring many of this segment’s POPdecline modestly in 2020, compared with fee contracts to increase the fee component and reduce ONEOK Partners’ direct commodity price risk. To mitigate the impact of its remaining commodity price exposure, ONEOK Partners has hedged a significant portion of the2019.

Our Natural Gas GatheringPipelines segment transports natural gas from more than 35 natural gas processing plants in Oklahoma. We completed pipeline expansions to provide increased westbound transportation services from the STACK area to multiple interstate pipeline delivery points in western Oklahoma and Processing segment’s commodity price risk for 2017 and 2018. This segment has substantial acreage dedications in some of the most productive areas of the Williston Basin and Mid-Continent region, specificallya 150 MMcf/d eastbound expansion from the STACK and SCOOP which helpsareas to mitigate the volumetric risk.an eastern Oklahoma interstate pipeline delivery point.


ThePermian Basin - We expect our Natural Gas Liquids segment’s earnings were approximately 90 percent fee-based in 2016. While ONEOK Partners is exposed to volumetric risk in this segment, this risk is partially mitigated through minimum volume commitments, which provide a minimum level of revenue regardless of the volumetric throughput. ONEOK Partners expects increasing demand from the petrochemical industry with the completion of ethylene production projects and NGL exports, which will require
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additional NGL transportation services that ONEOK Partners can provide without significant additional infrastructure needs or capital spending.

The Natural Gas Pipelines segment’s earnings were approximately 95 percent fee-basedbusiness segments to continue to benefit from increased production in 2016, generated primarilythe Permian Basin from firm demand charge contracts. Thisthe highly productive Delaware and Midland Basins. In our Natural Gas Liquids segment, continueswe are well-positioned in the Permian Basin through our West Texas LPG pipeline system. Due to developour

expansion of the system in the third quarter 2018 and new plant connections, volumes increased in 2019, compared with 2018. We expect volumes to continue to increase on our West Texas LPG pipeline system as our previously announced second and third expansions are completed, which will increase the mainline capacity out of the Permian Basin by 80 MBbl/d in the first quarter 2020 and 40 MBbl/d in the first quarter 2021, respectively, as well as connect our West Texas LPG pipeline with our Arbuckle II pipeline in north Texas. In addition, we recently announced the fourth expansion of our West Texas LPG pipeline system by 100 MBbl/d, which is expected to be completed in the second quarter 2021. These projects are expected to grow ONEOK Partners’ fee-based earnings, such as itsposition our West Texas LPG pipeline system for significant NGL volume growth and are backed by long-term acreage and/or plant dedications.

In our Natural Gas Pipelines segment, our Roadrunner joint venture and our WesTex pipeline are well-positioned to serve growth in the Permian Basin. The Roadrunner pipeline connects with our existing natural gas pipeline and storage infrastructure in Texas and, together with our completed WesTex intrastate natural gas pipeline expansion project, both of which are fully subscribed with 25-year firm demand charge, fee-based agreements. We expect additional demandcreates future opportunities for ONEOK Partners’ servicesus to deliver natural gas to power plants currently fueled by coalMexico and transport natural gas to other markets in the region.

Gulf Coast - Demand for NGLs is expected to increase at the Mont Belvieu, Texas, NGL market center as new world-scale ethylene production projects, petrochemical plant expansions and NGL export facilities continue to be completed. We are constructing our Arbuckle II pipeline to support increasedexpected supply growth and transport NGLs to the Gulf Coast market center and have announced an expansion of our Arbuckle II pipeline to a total capacity of 500 MBbl/d. NGL supply growth and other new NGL pipelines recently completed or being constructed, including our Elk Creek and West Texas LPG pipeline projects, are increasing NGL deliveries to Mont Belvieu, Texas. While we have significant NGL fractionation and storage assets in this area, additional capacity is needed to accommodate expected volume growth. To respond to this need, we are constructing two additional 125 MBbl/d fractionators with related infrastructure in Mont Belvieu, Texas, MB-4 and MB-5, which are both fully contracted. In December 2019, we completed construction of 75 MBbl/d of the MB-4 capacity, with the remaining 50 MBbl/d to be completed in the first quarter 2020, and MB-5 is expected to be completed in the first quarter 2021. Following the completion of MB-4 and MB-5, we expect our NGL fractionation capacity to be approximately 600 MBbl/d in the Gulf Coast and more than 1 MMBbl/d across our entire system. Our MB-5 project also includes system expansions that provide infrastructure capacity to support additional assets as we continue to evaluate opportunities for fractionation, storage and, potentially, export facilities to meet the supply and demand for natural gas exports to Mexico, as well as provide market connectivity to supply basins.NGLs.


See Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations, in this Annual Report for more information on our growth projects, results of operations, liquidity and capital resources.


BUSINESS STRATEGY


Our primary business strategy is to maximize dividend payout while maintainingmaintain prudent financial strength and flexibility while growing our fee-based earnings and dividends per share with a focus on safe, reliable, environmentally responsible, and legally compliant and sustainable operations for our customers, employees, contractors and the public through the following:
Operate in a safe, reliable, environmentally responsible and sustainable manner - environmental, safety and health continues to be a primary focus for us, and our emphasis on personal and process safety has produced improvements in the key indicators we track. We also continue to look for ways to reduce our environmental impact by conserving resources and utilizing more efficient technologies. In 2019, we were added to the Dow Jones Sustainability North America Index, which recognizes companies for industry-leading environmental, social and governance performance;
Pursue organic investments in our existing operating regions to support earnings growth - we expect our investment in capital projects to create stable earnings growth that positions us to grow our dividend. In 2019, we paid dividends of $3.53 per share, an increase of 9% compared with the prior year. Our dividend increase and expected future dividend growth is due primarily to earnings growth from capital projects;
Manage our balance sheet and maintain investment-grade credit ratings - we seek to maintain investment-grade credit ratings, fund capital-growth projects and begin to pay down debt. We expect to benefit from increasing cash flows from operations in 2020, which we expect to reduce leverage and fund capital-growth projects. At December 31, 2019, we had no borrowings outstanding under our $2.5 Billion Credit Agreement, $220 million of commercial paper outstanding and $21 million of cash and cash equivalents; and
Attract, select, develop, motivate, challenge and retain a diverse group of employees to support strategy execution - we continue to execute on our recruiting strategy that targets professional and field personnel in our operating areas. We also continue to focus on employee development efforts with our current employees and monitor our benefits and compensation package to remain competitive.
Provide reliable energy and energy-related services in a safe, reliable and environmentally responsible manner to our stakeholders through our ownership in ONEOK Partners - environmental, safety and health issues continue to be a primary focus for us, and our emphasis on personal and process safety has produced improvements in the key indicators we track. We also continue to look for ways to reduce our environmental impact by conserving resources and utilizing more efficient technologies;
Maximize dividend payout while maintaining prudent financial strength and flexibility - during 2016, cash dividends paid per share and cash distributions received from ONEOK Partners increased compared to 2015. Our excess cash gives us flexibility to take advantage of opportunities to create additional shareholder value. We expect our dividend payout to increase following the completion of the Merger Transaction with ONEOK Partners.
Attract, select, develop and retain a diverse group of employees to support strategy execution - we continue to execute on our recruiting strategy that targets professional and field personnel in our operating areas. We also continue to focus on employee development efforts with our current employees and monitor our benefits and compensation package to remain competitive.


NARRATIVE DESCRIPTION OF BUSINESS


We report operations in the following business segments:
Natural Gas Gathering and Processing;
Natural Gas Liquids; and
Natural Gas Pipelines.


Natural Gas Gathering and Processing


Overview -TheOur Natural Gas Gathering and Processing segment provides midstream services to contracted producers in North Dakota, Montana, Wyoming, Kansas and Oklahoma. ONEOK Partners provides exploration and production companies with gathering and processing services that allow them to move their raw (unprocessed) natural gas to market. Raw natural gas is gathered, compressed and transported through pipelines to ONEOK Partners’ processing facilities. In order for the raw natural gas to be accepted by the downstream market, it must have contaminants, such as water, nitrogen and carbon dioxide, removed and NGLs separated for further processing. Processed natural gas, usually referred to as residue natural gas, is then recompressed and delivered to natural gas pipelines and end users. The separated NGLs are in a mixed, unfractionated form and are sold and delivered through natural gas liquids pipelines to fractionation facilities for further separation.


Rocky Mountain region - The Williston Basin is located in portions of North Dakota and Montana and includes the oil-producing, NGL-rich Bakken Shale and Three Forks formations, and is an active drilling region. ONEOK Partners’Our completed growthcapital-growth projects including its Bear Creek natural gas processing plant and infrastructure project that was completed in August 2016,the Williston Basin have increased itsour gathering and processing capacity and allowed itallow us to capture increased natural gas production from new wells being drilled and previously flared natural gas previously flared by producers.production.

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The Powder River Basin is primarily located in Wyoming. This regionWyoming, which includes the NGL-rich Niobrara Shale and Frontier, Turner and Sussex formations where ONEOK Partners provideswe provide gathering and processing services to customers in the southeasteastern portion of Wyoming.


Mid-Continent region - ONEOK Partners’The Mid-Continent region is an active drilling region and includes the oil-producing, NGL-rich STACK and SCOOP areas in the Anadarko Basin and the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations of Oklahoma and Kansas;Kansas, and the Hugoton and Central Kansas Uplift Basins of Kansas. Producers are actively drilling in the NGL-rich STACK and SCOOP areas where ONEOK Partners has substantial acreage dedicated to it.


Revenues - Revenues for this segment are derived primarily from the following types of contracts:
POP with fee-based components - Under this type of contract, ONEOK Partners charges fees for gathering, treating, compressing and processing the producer’s natural gas. ONEOK Partners also generally purchases the producer’s raw natural gas, which it processes into residue natural gas and NGLs, then it sells these commodities and associated condensate to downstream customers. ONEOK Partners remits sales proceeds to the producer according to the contractual terms and retains its portion. This type of contract represented approximately 94 percent and 90 percent of contracted volumes in this segment for 2016 and 2015, respectively. There are a variety of factors that directly affect ONEOK Partners’ POP with fee revenues, including:
the price of natural gas, crude oil and NGLs;
nggppropertygraphica07.gif
the composition of the natural gas and NGLs produced;
the fees ONEOK Partners charges for its services; and
the volume produced.
Over time as ONEOK Partners’ contracts are renewed or restructured, it has generally increased the fee components. As a result, ONEOK Partners’ mix of commodity and fee-based earnings continues to change as volumes naturally decline on older contracts where it retains a higher percent of proceeds and volumes increase on contracts with higher fee components. Additionally, under certain POP with fee contracts ONEOK Partners’ fee revenues may increase or decrease if production volumes, delivery pressures or commodity prices change relative to specified thresholds.
Fee-only
Property - Under this type of contract, ONEOK Partners is paid a fee for the services it provides, based on volumes gathered, processed, treated and/or compressed. ONEOK Partners’ fee-only contracts represented approximately 6 percent and 10 percent of contracted volumes in this segment for 2016 and 2015, respectively.

Property - TheOur Natural Gas Gathering and Processing segment owns the following assets:
approximately 11,300 miles and 7,70018,900 miles of natural gas gathering pipelines in the Mid-Continent and Rocky Mountain regions, respectively;pipelines;
nineten natural gas processing plants with approximately 785 MMcf/1.0 Bcf/d of processing capacity in the Mid-Continent region, and 12 natural gas processing plants with approximately 1,045 MMcf/1.5 Bcf/d of processing capacity in the Rocky Mountain region; and
approximately 1514 MBbl/d of natural gas liquidsNGL fractionation capacity at various natural gas processing plantsplants.


In addition, we have access to up to 200 MMcf/d of processing capacity in the Rocky Mountain region.Mid-Continent region through a long-term processing services agreement with an unaffiliated third party.


We are in the process of expanding our Bear Creek plant by 200 MMcf/d and recently announced plans to construct our Demicks Lake III natural gas processing plant, with capacity of 200 MMcf/d, in the core of the Williston Basin. The additional capacity from these projects is excluded from the assets listed above.

See “Recent Developments” in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations, in this Annual Report for more information on our growth projects.

Sources of Earnings - Earnings for this segment are derived primarily from the following types of service contracts:
POP with fee contracts with no producer take-in-kind rights - We purchase raw natural gas and charge contractual fees for providing midstream services, which include gathering, treating, compressing and processing the producer’s natural gas. After performing these services, we sell the commodities and remit a portion of the commodity sales proceeds to the producer less our contractual fees. This type of contract represented 63% and 60% of supply volumes in this segment for 2019 and 2018, respectively.
POP with fee contracts with producer take-in-kind rights - We purchase a portion of the raw natural gas stream, charge fees for providing the midstream services listed above, return primarily the residue natural gas to the producer, sell the remaining commodities and remit a portion of the commodity sales proceeds to the producer less our contractual fees. This type of contract represented 33% and 36% of supply volumes in this segment for 2019 and 2018, respectively.
Fee-only - Under this type of contract, we charge a fee for the midstream services we provide, based on volumes gathered, processed, treated and/or compressed. Our fee-only contracts represented 4% of supply volumes in this segment in 2019 and 2018.

For commodity sales, we contract to deliver residue natural gas, condensate and/or unfractionated NGLs to downstream customers at a specified delivery point. Our sales of NGLs are primarily to our affiliate in the Natural Gas Liquids segment.

Utilization - The utilization rates for ONEOK Partners’our natural gas processing plants were approximately 76 percent84% and 83% for both 20162019 and 2015. ONEOK Partners calculates2018, respectively. We calculate utilization rates using a weighted-average approach, adjusting for the dates that assets were placed in service.


Unconsolidated Affiliates - TheOur Natural Gas Gathering and Processing segment includes the following unconsolidated affiliates:
49 percent49% ownership interest in Bighorn Gas Gathering, which operates a coal-bed methane gathering systemgathers dry natural gas produced in the Powder River Basin;
37 percent42.6% ownership interest in Fort Union Gas Gathering, which gathers coal-bed methanedry natural gas produced in the Powder River Basin and delivers it to the interstate pipeline system;
35 percent35% ownership interest in Lost Creek Gathering Company, which gathers natural gas produced from conventional dry natural gas wells in the Wind River Basin of central Wyoming and delivers it to the interstate pipeline system; and
10 percent10.2% ownership interest in Venice Energy Services Co., a natural gas processing facility near Venice, Louisiana.


See Note NM of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of our unconsolidated affiliates.


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Market Conditions and Seasonality -Supply - Rocky Mountain region - In the Williston Basin, natural gas volumes continued to grow in 2016, driven primarily by producer development of Bakken Shale crude oil wells, which also produce associated natural gas containing significant quantities of NGLs. The number of well connections in 2016 decreased, compared with 2015, due to reduced drilling and completion activity by producers and continued low commodity prices. ONEOK Partners’ natural gas gathered and processed volumes in the Williston Basin increased in 2016, compared with 2015, despite the reductions in producer drilling activity, due to the following:
capturing additional natural gas previously flared by producers through natural gas compression and processing capacity placed in service in late 2015 and projects completed in 2016;
producers focusing their drilling and completion in the most productive areas where ONEOK Partners has significant gathering and processing assets, which typically produce at higher initial production rates compared with other areas and have higher natural gas to oil ratios; and
continued improvements in production by producers due to enhanced completion techniques and more efficient drilling rigs.

In 2017, we expect volume growth in the Williston Basin from the projects and production activities discussed above to be partially offset by natural production declines.

Mid-Continent region - In the Mid-Continent region, ONEOK Partners has significant natural gas gathering and processing assets in Oklahoma and Kansas. With the emerging STACK and SCOOP areas, we anticipate increased producer activity in the Mid-Continent, where ONEOK Partners has substantial acreage dedications in these productive areas. We expect ONEOK Partners’ average natural gas volumes to grow in 2017 due to continued drilling and completion activity, offset partially by the natural volume declines from existing wells connected to ONEOK Partners’ system.

Demand-Demand for gathering and processing services is dependent on natural gas production by producers, which is driven by the strength of the economy; natural gas, crude oil and NGL prices; and the demand for each of these products from end users. The Natural Gas Gathering and Processing segment’s customers are generally crude oil and natural gas producers who have proven reserves or are currently producing natural gas in areas within ONEOK Partners’ existing infrastructure and need gathering and processing services. Additionally, demand is impacted by the weather, which is discussed below under “Seasonality.”

Rocky Mountain region - Demand for ONEOK Partners’ gathering and processing services in the Williston Basin has remained strong even as crude oil prices remained low. Requirements in North Dakota for producers to reduce natural gas flaring have increased the need for ONEOK Partners’ services to capture, gather and process this natural gas. ONEOK Partners has approximately 200 MMcf/d of available processing capacity in the Williston Basin.

Mid-Continent region - As producers continue to develop the STACK and SCOOP areas of the Anadarko Basin, we expect increased demand for ONEOK Partners’ services from producers. ONEOK Partners has approximately 100 MMcf/d of available processing capacity in Oklahoma.

Commodity Prices - While ONEOK Partners has significantly reduced its direct exposure to commodity prices in this segment and its earnings are primarily fee-based, the commodity price environment has resulted in a reduction of producer drilling activity and well completions in 2016 and 2015.

See discussion regarding our commodity price risk and related hedging activities under “Commodity Price Risk” in Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Seasonality - Cold temperatures usually increase demand for natural gas and certain NGL products such as propane, the main heating fuels for homes and businesses. Warm temperatures usually increase demand for natural gas used in gas-fired electric generators for residential and commercial cooling, as well as agriculture-related equipment like irrigation pumps and crop dryers. During periods of peak demand for a certain commodity, prices for that product typically increase.

Extreme weather conditions and seasonal temperature changes impact the volumes and composition of natural gas gathered and processed. Freeze-offs are a phenomenon where water produced with natural gas freezes at the wellhead or within the gathering system. This causes a temporary interruption in the flow of natural gas. All of ONEOK Partners’ operations may be affected by other weather conditions that may cause a loss of electricity at ONEOK Partners’ facilities or prevent access to certain locations that affect a producer’s ability to complete wells or ONEOK Partners’ ability to connect those wells to its systems.

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Competition- ONEOK Partners competes for natural gas supplywith major integrated oil companies, independent exploration and production companies that have gathering and processing assets, pipeline companies and their affiliated marketing companies, and other midstream gatherers and processors. The factors that typically affect ONEOK Partners’ ability to compete for natural gas supply are:
quality of services provided;
producer drilling activity;
proceeds remitted and/or fees charged under its gathering and processing contracts;
location of its gathering systems relative to those of its competitors;
location of its gathering systems relative to drilling activity;
operating pressures maintained on its gathering systems;
efficiency and reliability of its operations;
delivery capabilities for natural gas and NGLs that exist in each system and plant location; and
cost of capital.

Competition for natural gas gathering and processing services continues to increase as new infrastructure projects are completed to address increased production from shale and other resource areas. In response to these changing industry conditions, ONEOK Partners continues to evaluate opportunities to increase earnings and cash flows, and reduce risk by:
improving natural gas processing efficiency;
reducing operating costs;
consolidating assets;
decreasing commodity price exposure; and
restructuring low-margin contracts.

Customers - ONEOK Partners’ natural gas gathering and processing customers include both large integrated and independent exploration and production companies. See discussion regarding ONEOK Partners’ customer credit risk under “Counterparty Credit Risk” in Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Government Regulation -The FERC traditionally has maintained that a natural gas processing plant is not a facility for the transportation or sale of natural gas in interstate commerce and, therefore, is not subject to jurisdiction under the Natural Gas Act. Although the FERC has made no specific declaration as to the jurisdictional status of ONEOK Partners’our natural gas processing operations or facilities, itsour natural gas processing plants are primarily involved in extracting NGLs and, therefore, are exempt from FERC jurisdiction. The Natural Gas Act also exempts natural gas gathering facilities from the jurisdiction of the FERC. We believe ONEOK Partners’our natural gas gathering facilities and operations meet the criteria used by the FERC for nonjurisdictional natural gas gathering facility status. Interstate transmission facilities remain subject to FERC jurisdiction. The FERC has historically distinguished between these two types of facilities, either interstate or intrastate, on a fact-specific basis. ONEOK Partners transportsWe transport residue natural gas from itscertain of our natural gas processing plants to interstate pipelines in accordance with Section 311(a) of the Natural Gas Policy Act. Oklahoma, Kansas, Wyoming, Montana and North Dakota also have statutes regulating, to varying degrees, the gathering of natural gas in those states. In each state, regulation is applied on a case-by-case basis if a complaint is filed against the gatherer with the appropriate state regulatory agency.


See further discussion in the “Regulatory, Environmental and Safety Matters” section.



Natural Gas Liquids


Overview -The Our Natural Gas Liquids segment owns and operates facilities that gather, fractionate, treat and distribute NGLs and store NGL products, primarily in Oklahoma, Kansas, Texas, New Mexico and the Rocky Mountain region, where it provideswhich includes the Williston, Powder River and DJ Basins. We provide midstream services to producers of NGLs and deliversdeliver those products to the two primary market centers,centers: one in the Mid-Continent in Conway, Kansas, and the other in the Gulf Coast in Mont Belvieu, Texas. This segment ownsWe own or hashave an ownership interest in FERC-regulated natural gas liquidsNGL gathering and distribution pipelines in Oklahoma, Kansas, Texas, New Mexico, Montana, North Dakota, Wyoming and Colorado, and terminal and storage facilities in Missouri, Nebraska, Iowa and Illinois. ONEOK Partners also owns FERC-regulatedThe majority of the pipeline-connected natural gas liquidsprocessing plants in the Williston Basin, Oklahoma, Kansas and the Texas Panhandle are connected to our NGL gathering systems. We own and operate truck- and rail-loading and -unloading facilities connected to our NGL fractionation and pipeline assets. We also own FERC-regulated NGL distribution and refined petroleum products pipelines in Kansas, Missouri, Nebraska, Iowa, Illinois and Indiana that connect itsour Mid-Continent assets with Midwest markets, including Chicago, Illinois. The majorityA portion of the pipeline-connected natural gas processing plants in Oklahoma,our ONEOK North System transports refined petroleum products, including unleaded gasoline and diesel, from Kansas and the Texas Panhandle are connected to its gathering systems. ONEOK Partners owns and operates truck- and rail-loading and -unloading facilities connected to its natural gas liquids fractionation and pipeline assets.Iowa.

Most natural gas produced at the wellhead contains a mixture of NGL components, such as ethane, propane, iso-butane, normal butane and natural gasoline. The NGLs that are separated from the natural gas stream at natural gas processing plants remain in
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a mixed, unfractionated form until they are gathered, primarily by pipeline, and delivered to fractionators where the NGLs are separated into NGL products. These NGL products are then stored or distributed to the
Property - Our Natural Gas Liquids segment’s customers, such as petrochemical manufacturers, heating fuel users, ethanol producers, refineries, exporterssegment owns the following assets:
8,380 miles of gathering pipelines with peak capacity of 1,820 MBbl/d, including 5,550 miles of FERC-regulated pipelines with peak capacity of 920 MBbl/d;
4,490 miles of distribution pipelines with peak capacity of 1,400 MBbl/d, including 4,460 miles of FERC-regulated pipelines with peak capacity of 1,360 MBbl/d;
eight NGL fractionators with combined operating capacity of 870 MBbl/d (includes interests in our proportional share of operating capacity), including 520 MBbl/d in the Mid-Continent region and 350 MBbl/d in the Gulf Coast region;
one isomerization unit with operating capacity of 10 MBbl/d;
one ethane/propane distributors.splitter with operating capacity of 40 MBbl/d;
six NGL storage facilities with operating storage capacity of 20 MMBbl; and
eight NGL product terminals.


RevenuesIn addition, we lease 10 MMBbl of annual pipeline capacity near our ONEOK North System and have access to 5 MMBbl of combined NGL storage capacity at facilities in Kansas and Texas and 60 MBbl/d of NGL fractionation capacity in the Gulf Coast through service agreements.

Our uncompleted growth projects are excluded from the assets listed above and include:
gathering pipelines, including expansions, with combined operating capacity of 880 MBbl/d;
the MB-5 fractionator in the Gulf Coast with operating capacity of 125 MBbl/d;
remaining fractionation capacity on the MB-4 fractionator in the Gulf Coast of 50 MBbl/d; and
additional fractionation capacity in the Mid-Continent of 65 MBbl/d.

See “Recent Developments” in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations, in this Annual Report for themore information on our growth projects.

Sources of Earnings - Earnings for our Natural Gas Liquids segment are derived primarily from commodity sales and fee-based services that ONEOK Partners provides to its customers and from the physical optimization of its assets. This segmentservices. We also purchasespurchase NGLs and condensate from third parties, as well as from theour Natural Gas Gathering and Processing segment. This segment’s fee-based services have increased due primarily to new supply connections, expansion of existing connections and the completion of capital-growth projects. This segment’sOur business activities are categorized as exchangefollows:
Exchange services transportation and storage services, and optimization and marketing, which are defined as follows:
ONEOK Partners’ exchange services- We utilize itsour assets to gather, fractionate and/ortransport, treat and transportfractionate unfractionated NGLs, thereby converting them into marketable NGL products shippeddelivered to a market center or customer-designated location. Many of these exchange volumes are under contracts with minimum volume commitments that provide a minimum level of revenues regardless of volumetric throughput. ONEOK Partners’Our exchange services activities are primarily fee-based and include some rate-regulated tariffs; however, itwe also capturescapture certain product price differentials through the fractionation process.
ONEOK Partners’ transportationTransportation and storage services include the- We transport of NGL products and refined petroleum products, primarily under FERC-regulated tariffs. Tariffs specify the maximum rates ONEOK Partnerswe may charge itsour customers and the general terms and conditions for NGL transportation service on itsour pipelines. ONEOK Partners’Our storage activities consist primarily of fee-based NGL storage services at itsour Mid-Continent and Gulf Coast storage facilities.
ONEOK Partners’ optimizationOptimization and marketing activities- We utilize itsour assets, contract portfolio and market knowledge to capture location, product and seasonal price differentials. ONEOK Partnersdifferentials through the purchase and sale of NGLs and NGL products. We primarily transportstransport NGL products between Conway, Kansas, and Mont Belvieu, Texas, to capture the location price differentials between the two market centers. ONEOK Partners’Our marketing activities also include utilizing its natural gas liquidsour NGL storage facilities to capture seasonal price differentials. A growing portion of ONEOK Partners’our marketing activities serves truck and rail markets. ONEOK Partners’Our isomerization activities capture the price differential when normal butane is converted into the more valuable iso-butane at itsour isomerization unit in Conway, Kansas.

Supply growth from the development of NGL-rich areas and increased capacity available on pipelines that connect the Mid-Continent and Gulf Coast resulted in NGL price differentials remaining narrow between the Mid-Continent market center at Conway, Kansas, and the Gulf Coast market center at Mont Belvieu, Texas. We expect these narrow price differentials to persist between these two market centers until demand for NGLs increases from petrochemical companies and exporters, which we anticipate to begin in the second half of 2017.

Property -The Natural Gas Liquids segment owns the following assets:
approximately 2,800 miles of non-FERC-regulated natural gas liquids gathering pipelines with peak capacity of approximately 800 MBbl/d;
approximately 170 miles of non-FERC-regulated natural gas liquids distribution pipelines with peak transportation capacity of approximately 66 MBbl/d;
approximately 4,300 miles of FERC-regulated natural gas liquids gathering pipelines with peak capacity of approximately 683 MBbl/d;
approximately 4,200 miles of FERC-regulated natural gas liquids and refined petroleum products distribution pipelines with peak capacity of 993 MBbl/d;
one natural gas liquids fractionator in Oklahoma with operating capacity of approximately 210 MBbl/d, two natural gas liquids fractionators in Kansas with combined operating capacity of 280 MBbl/d and two natural gas liquids fractionators in Texas with combined operating capacity of 150 MBbl/d;
80 percent ownership interest in one natural gas liquids fractionator in Texas with ONEOK Partners’ proportional share of operating capacity of approximately 128 MBbl/d;
interest in one natural gas liquids fractionator in Kansas with ONEOK Partners’ proportional share of operating capacity of approximately 11 MBbl/d;
one isomerization unit in Kansas with operating capacity of 9 MBbl/d;
six natural gas liquids storage facilities in Oklahoma, Kansas and Texas with operating storage capacity of approximately 22.2 MMBbl;
eight natural gas liquids product terminals in Nebraska, Iowa and Illinois;
above- and below-ground storage facilities associated with ONEOK Partners’ FERC-regulated natural gas liquids pipeline operations in Iowa, Illinois, Nebraska and Kansas with combined operating capacity of 978 MBbl; and
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one ethane/propane splitter in Texas with operating capacity of 32 MBbl/d of purity ethane and 8 MBbl/d of propane.


In addition, ONEOK Partners leases approximately 3.0 MMBblmany of combinedour exchange services contracts, we purchase the unfractionated NGLs at the tailgate of the processing plant and deduct contractual fees related to the transportation and fractionation services we must perform before we can sell them as NGL storage capacity at facilitiesproducts. To the extent we hold unfractionated NGLs in Kansasinventory, the related contractual fees will not be recognized until the unfractionated inventory is fractionated and Texas and has access to 60 MBbl/d of natural gas liquids fractionation capacity in Texas through a fractionation service agreement.sold.


Utilization -The utilization rates for ONEOK Partners’our various assets, including leased assets, have been impacted by ethane rejection. The utilization rates for 20162019 and 2015,2018, respectively, were as follows:
its non-FERC-regulated natural gas liquidsour NGL gathering pipelines were approximately 66 percent and 65 percent;78% in both years;
its FERC-regulated natural gas liquids gathering pipelines were approximately 77 percent and 75 percent;
its FERC-regulated natural gas liquidsour NGL distribution pipelines were approximately 56 percent63% and 43 percent;59%; and
its natural gas liquidsour NGL fractionators were approximately 70 percent84% and 66 percent.85%.


ONEOK Partners calculatesWe calculate utilization rates using a weighted-average approach, adjusting for the dates that assets were placed in service. ONEOK Partners’Our fractionation utilization rate reflects approximate proportional capacity associated with itsour ownership interests.


Unconsolidated Affiliates - TheOur Natural Gas Liquids segment includes the following unconsolidated affiliates:
50 percent50% ownership interest in Overland Pass Pipeline Company, which operates an interstate natural gas liquidsNGL pipeline system extending approximately 760 miles, originating in Wyoming and Colorado and terminating in Kansas;
50 percent50% ownership interest in Chisholm Pipeline Company, which operates an interstate natural gas liquidsNGL pipeline system extending approximately 185 miles from origin points in Oklahoma and terminating in Kansas; and
50 percent50% ownership interest in Heartland Pipeline Company, which operates a terminal and pipeline system that transports refined petroleum products in Kansas, Nebraska and Iowa.


See Note NM of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of unconsolidated affiliates.


Market Conditions and Seasonality -Supply-The unfractionated NGLs that ONEOK Partners gathers and transports originate primarily from natural gas processing plants connected to ONEOK Partners’ gathering systems in Oklahoma, Kansas, Texas, New Mexico and the Rocky Mountain region. The Natural Gas Liquids segment is connected to more than 100 third-party natural gas processing plants in the Mid-Continent region, is one of the primary NGL takeaway providers for the emerging STACK and SCOOP areas and is one of the primary takeaway providers for the Williston Basin with the Bakken NGL Pipeline. ONEOK Partners’ fractionation operations receive NGLs from a variety of processors and pipelines, including its affiliates, located in these regions. Supply for the Natural Gas Liquids segment depends on crude oil and natural gas drilling and production activities by producers, the decline rate of existing production, natural gas processing plant economics and capabilities, and the NGL content of the natural gas that is produced and processed in the areas in which ONEOK Partners operates.

Supply growth has resulted in available ethane supplies that are greater than the petrochemical industry’s current demand. As a result, low or unprofitable price differentials between ethane and natural gas have resulted in ethane rejection at most of ONEOK Partners’ and its customers’ natural gas processing plants connected to its natural gas liquids gathering system in the Mid-Continent and Rocky Mountain regions, which reduced the ethane component of natural gas liquids volumes gathered, fractionated, transported and sold across its assets. Through ethane rejection, natural gas processors leave some of the ethane component in the natural gas stream sold at the tailgate of natural gas processing plants. Ethane rejection levels by natural gas processors delivering to ONEOK Partners’ natural gas liquids gathering system have continued to fluctuate, averaging approximately 175 MBbl/d in 2016. While the volume of ethane produced increased modestly during 2016, compared with 2015, a portion of the fees associated with those volumes gathered and fractionated was previously being earned under contracts with minimum volume obligations. We expect ethane rejection levels to continue to fluctuate in 2017 as the market begins to balance ethane supply and demand and as the price differentials between ethane and natural gas change. We expect ethane recovery levels to increase as ethylene producers and NGL exporters increase their capacity to consume and export additional ethane volumes. Expansion of the petrochemical industry in the United States is expected to increase ethane demand in the second half of 2017. International demand for NGLs, particularly ethane and propane, also is expected to increase.

Demand - Demand for NGLs and the ability of natural gas processors to successfully and economically sustain their operations affect the volume of unfractionated NGLs produced by natural gas processing plants, thereby affecting the demand for NGL gathering, fractionation and transportation services. Natural gas and propane are subject to weather-related seasonal demand. Other NGL products are affected by economic conditions and the demand associated with the various industries that utilize the
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commodity, such as butanes and natural gasoline used by the refining industry as blending stocks for motor fuel, denaturant for ethanol and diluents for crude oil. Ethane, propane, normal butane and natural gasoline are used by the petrochemical industry to produce chemical products, such as plastic, rubber and synthetic fibers. Several petrochemical companies are constructing new plants, plant expansions, additions or enhancements that improve the light-NGL feed capability of their facilities due primarily to the increased supply and attractive price of ethane, compared with crude oil-based alternatives, as a petrochemical feedstock in the United States. The demand is expected to increase beginning in the second half of 2017 when many of the new petrochemical plants and plant modifications are expected to be completed. In addition, we expect increased international demand for ethane, propane and butane to provide opportunities to increase fee-based earnings in ONEOK Partners’ exchange and storage services and marketing activities.

Commodity Prices - The Natural Gas Liquids segment provides primarily fee-based services. However, ONEOK Partners is exposed to market risk associated with changes in the price of NGLs; the location differential between the Mid-Continent, Chicago, Illinois, and Gulf Coast regions; and the relative price differential between natural gas, NGLs and individual NGL products, which affect its NGL purchases and sales, and its exchange, storage, transportation, optimization and marketing financial results. Supply growth from the development of NGL-rich areas and increased capacity available on pipelines that connect the Mid-Continent and Gulf Coast market centers resulted in NGL price differentials remaining narrow between the Mid-Continent market center at Conway, Kansas, and the Gulf Coast market center at Mont Belvieu, Texas. NGL storage revenue may be affected by price volatility and forward pricing of NGL physical contracts versus the price of NGLs on the spot market.

Seasonality - ONEOK Partners’ natural gas liquids fractionation and pipeline operations typically experience some seasonal variation. Some NGL products stored and transported through ONEOK Partners’ assets are subject to weather-related seasonal demand, such as propane, which can be used for heating during the winter and for agricultural purposes such as crop drying in the fall. Demand for butanes and natural gasoline, which are primarily used by the refining industry as blending stocks for motor fuel, denaturant for ethanol and diluents for crude oil, may also be subject to some variability during seasonal periods when certain government restrictions on motor fuel blending products change. The ability of natural gas processors to produce NGLs also is affected by weather. Extreme weather conditions and ground temperature changes impact the volumes of natural gas gathered and processed and NGL volumes gathered, transported and fractionated. Power interruptions, inaccessible well sites as a result of storms or freeze-offs, a phenomenon where water produced from natural gas freezes at the wellhead or within the gathering system, cause a temporary interruption in the flow of natural gas and NGLs.

Competition -The Natural Gas Liquids segment competes with other fractionators, intrastate and interstate pipeline companies, storage providers, and gatherers and transporters for NGL supply in the Permian Basin and Rocky Mountain, Mid-Continent and Gulf Coast regions. The factors that typically affect ONEOK Partners’ ability to compete for NGL supply are:
quality of services provided;
producer drilling activity;
the petrochemical industry’s level of capacity utilization and feedstock requirements;
fees charged under its contracts;
current and forward NGL prices;
location of its gathering systems relative to its competitors;
location of its gathering systems relative to drilling activity;
proximity to NGL supply areas and markets;
efficiency and reliability of its operations;
receipt and delivery capabilities that exist in each pipeline system, plant, fractionator and storage location; and
cost of capital.

ONEOK Partners has responded to these factors by making capital investments to access new supplies; increasing gathering, fractionation and distribution capacity; increasing storage, withdrawal and injection capabilities; and reducing operating costs so that it may compete effectively. ONEOK Partners’ competitors continue to invest in natural gas liquids pipeline and fractionation infrastructure to address the growing NGL supply and petrochemical demand. As ONEOK Partners’ growth projects and those of its competitors have alleviated constraints between the Mid-Continent and Gulf Coast NGL market centers, we expect the narrow location price differentials between the two locations to continue. In addition, ONEOK Partners’ competitors’ natural gas liquids infrastructure projects provide NGL supply from the Rocky Mountain, Marcellus and Utica basins into the Gulf Coast market center, which affects NGL prices and competes with and could displace NGL supply volumes from the Mid-Continent and Rocky Mountain regions where ONEOK Partners’ assets are located. We believe ONEOK Partners’ natural gas liquids fractionation, pipelines and storage assets are located strategically, connecting diverse supply areas to market centers.

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Customers-The Natural Gas Liquids segment’s customers are primarily NGL and natural gas gathering and processing companies; major and independent crude oil and natural gas production companies; propane distributors; ethanol producers; and petrochemical, refining and NGL marketing companies. See discussion regarding ONEOK Partners’ customer credit risk under “Counterparty Credit Risk” in Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Government Regulation - The operations and revenues of ONEOK Partners’ natural gas liquidsour NGL pipelines are regulated by various state and federal government agencies. ItsOur interstate natural gas liquidsNGL pipelines are regulated by the FERC, which has authority over the terms and conditions of service; rates, including depreciation and amortization policies; and initiation of service. In Oklahoma, Kansas and Texas, certain aspects of ONEOK Partners’our intrastate natural gas liquidsNGL pipelines that provide common carrier service are subject to the jurisdiction of the OCC, KCC and RRC, respectively.

PHMSA has asserted jurisdiction over certain portions of ONEOK Partners’ fractionation facilities in Bushton, Kansas, that it believes are subject to its jurisdiction. ONEOK Partners has objected to the scope of PHMSA’s jurisdiction and is seeking resolution of this matter. ONEOK Partners does not anticipate that the cost of compliance will have a material adverse effect on its consolidated results of operations, financial position or cash flows.


See further discussion in the “Regulatory, Environmental and Safety Matters” section.


Natural Gas Pipelines


Overview - TheOur Natural Gas Pipelines segment provides transportation and storage services to end users through ONEOK Partners’its wholly owned assets and its 50 percent50% ownership interests in Northern Border Pipeline and Roadrunner. Phase I and Phase II of the Roadrunner pipeline were completed in March and October 2016, respectively.


Interstate Pipelines - ONEOK Partners’Our interstate pipelines are regulated by the FERC and are located in North Dakota, Minnesota, Wisconsin, Illinois, Indiana, Kentucky, Tennessee, Oklahoma, Texas and New Mexico. ONEOK Partners’Our interstate pipeline companies include:
Midwestern Gas Transmission, which is a bidirectional system that interconnects with Tennessee Gas Transmission Company’s pipeline near Portland, Tennessee, and with several interstate pipelines that have access to both the Utica Shale and the Marcellus Shale at the Chicago Hub near Joliet, Illinois;
Viking Gas Transmission, which is a bidirectional system that interconnects with a TransCanada Corporation pipeline at the United States border near Emerson, Canada, and ANR Pipeline Company near Marshfield, Wisconsin;
Guardian Pipeline, which interconnects with several pipelines at the Chicago Hub near Joliet, Illinois, and with local natural gas distribution companies in Wisconsin; and
OkTex Pipeline, which has interconnections with several pipelines in Oklahoma, Texas and New Mexico.


Intrastate Pipelines - ONEOK Partners’Our intrastate natural gas pipeline assets in Oklahoma transport natural gas through the state and have access to the major natural gas production areas in the Mid-Continent region, which include the emerging STACK and SCOOP areas in the Anadarko Basin and the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations. ONEOK Partners’ intrastate natural gas pipeline assets in Oklahoma serve end-use markets, such as local distribution companies and power generation companies. In Texas, ONEOK Partners’our intrastate natural gas pipelines are connected to the major natural gas producing formations in the Texas Panhandle, including the Granite Wash formation and Delaware and Cline producing formationsMidland Basins in the Permian Basin. These pipelines are capable of transporting natural gas throughout the western portion of Texas, including the Waha Hubarea where other pipelines may be accessed for transportation to western markets, exports to Mexico, the Houston Ship Channel market to the east and the Mid-Continent market to the north. ONEOK Partners’Our intrastate natural gas pipeline assets also have access to the Hugoton and Central Kansas Uplift Basins in Kansas.


The Roadrunner pipeline transports
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Property - Our Natural Gas Pipelines segment owns the following assets:
1,500 miles of FERC-regulated interstate natural gas from the Permian Basin in West Texas to the Mexican border near El Paso, Texas,pipelines with 3.5 Bcf/d of peak transportation capacity;
5,100 miles of state-regulated intrastate transmission pipelines with peak transportation capacity of 4.3 Bcf/d; and is fully subscribed with 25-year firm demand charge, fee-based agreements. The Roadrunner pipeline connects with ONEOK Partners’ existing
six underground natural gas pipelinestorage facilities with 52.2 Bcf of total active working natural gas storage capacity.

Our storage includes two underground natural gas storage facilities in Oklahoma, two underground natural gas storage facilities in Kansas and two underground natural gas storage facilities in Texas.

Sources of Earnings - Earnings in this segment are derived primarily from transportation and storage infrastructure in Texas and, together with its WesTex intrastate natural gas pipeline expansion project, creates a platform for future opportunities to deliver natural gas supply to Mexico. If tariffs, border taxes or other measures assessed on cross-border transactions with Mexico are implemented, we do not expect them to materially impact ONEOK Partners or Roadrunner. Roadrunner’s long-term firm demandservices.

Our transportation service contracts provide markets in Mexico access to upstream supply basins in West Texas and the Mid-Continent region, which adds location and price diversity to their supply mix and supports the plan of Mexico’s national electric utility, Comisión Federal de Electricidad, to replace oil-fueled power plants with natural gas-fueled power plants, which are more economical and produce fewer GHG emissions.
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Transportation Rates - ONEOK Partners’ transportation contracts for its regulated natural gas services are based upon rates stated in the respective tariffs. The tariffs provide both the general terms and conditions for the facilities and the maximum allowed rates customers can be charged by type of service, which may be discounted to meet competition if necessary. The rates are established at FERC or the appropriate state jurisdictional agencies. The earnings are primarily fee-based from the following types of services:
Firm service - Customers reserve a fixed quantity of pipeline capacity for a specified period of time, which obligates the customer to pay regardless of usage. Under this type of contract, the customer pays a monthly fixed fee and incremental fees, known as commodity charges, which are based on the actual volumes of natural gas they transport or store. In addition, ONEOK Partners may retain a percentage of fuel in-kind based on the volumes of natural gas transported. Under the firm service contract, the customer generally is guaranteed access to the capacity they reserve.
Interruptible service - Under interruptible service transportation agreements, the customer may utilize available capacity after firm service requests are satisfied. The customer is not guaranteed use of ONEOK Partners’our pipelines unless excess capacity is available. Customers

Our regulated natural gas transportation services contracts are based upon rates stated in the respective tariffs, which have generally been established through shipper specific negotiation, discounts and negotiated settlements. The rates are filed with FERC or the appropriate state jurisdictional agencies. In addition, customers typically are assessed fees, such as a commodity charge, and ONEOK Partnerswe may retain a percentage or specified volume of natural gas in-kind based on their actual usage.

Storage - ONEOK Partners ownsthe natural gas storage facilities located in Texas and Oklahoma that are connected to its intrastate natural gas pipelines. It also has underground natural gas storage facilities in Kansas. In Texas and Kansas, natural gas storage operations may be regulated by the state in which the facility operates and by the FERC for certain types of services. In Oklahoma, natural gas storage operations are not subject to rate regulation by the state and have market-based rate authority from the FERC for certain types of services.volumes transported.


Storage Rates - TheOur storage earnings are primarily fee-based from the following types of services:
Firm service - Customers reserve a specific quantity of storage capacity, including injection and withdrawal rights, and generally pay fixed fees based on the quantity of capacity reserved plus an injection and withdrawal fee. Firm storage contracts typically have terms longer than one year.
Park-and-loan service - An interruptible storage service offered to customers providing the ability to park (inject) or loan (withdraw) natural gas into or out of our storage, typically for monthly or seasonal terms. Customers reserve the

right to park or loan natural gas based on a specified quantity, including injection and withdrawal rights when capacity is available.


PropertyUtilization - The Natural Gas Pipelines segment owns the following assets:
approximately 1,500 miles of FERC-regulated interstate natural gas pipelines with approximately 3.5 Bcf/d of peak transportation capacity;
approximately 5,200 miles of state-regulated intrastate transmission pipelines with peak transportation capacity of approximately 3.4 Bcf/d; and
approximately 57.8 Bcf of total active working natural gas storage capacity.

ONEOK Partners’ storage includes three underground natural gas storage facilities in Oklahoma, two underground natural gas storage facilities in Kansas and two underground natural gas storage facilities in Texas.

Utilization - ONEOK Partners’Our natural gas pipelines were approximately 92 percent98% and 96% subscribed in both 20162019 and 2015,2018, respectively, and itsour natural gas storage facilities were 65 percent64% subscribed in 2016both 2019 and 71 percent subscribed in 2015.2018.


Unconsolidated Affiliates - TheOur Natural Gas Pipelines segment includes the following unconsolidated affiliates:
50 percent50% ownership interest in Northern Border Pipeline, which owns a FERC-regulated interstate pipeline that transports natural gas from the Montana-Saskatchewan border near Port of Morgan, Montana, and the Williston Basin in North Dakota to a terminus near North Hayden, Indiana.
50 percent50% ownership interest in Roadrunner, a bidirectional pipeline, which has the capacity to transport approximately 570 MMcf/d of natural gas from the Permian Basin in West Texas to the Mexican border near El Paso, Texas. ONEOK Partners isTexas, and has capacity to transport approximately 1.0 Bcf/d of natural gas from the Delaware Basin to the Waha area. We are the operator of Roadrunner.


See Note NM of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of unconsolidated affiliates.


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Market Conditions and Seasonality - Supply- The development of natural gas produced from shale resource areas has continued to increase available supply across North America and has caused location and seasonal price differentials to narrow in the regions where ONEOK Partners operates.

Interstate - Guardian Pipeline, Midwestern Gas Transmission and Viking Gas Transmission access supply from the major producing regions of the Mid-Continent, Rocky Mountains, Canada, Gulf Coast and the Northeast. The current supply of natural gas for Northern Border Pipeline is primarily sourced from Canada; however, as the Williston Basin supply area has developed, more natural gas supply from this area is being transported on Northern Border Pipeline to markets near Chicago. In addition, supply volumes from nontraditional natural gas production areas, such as the Marcellus and Utica shale areas in the Northeast, may compete with and displace volumes from the Mid-Continent, Rocky Mountain and Canadian supply sources in ONEOK Partners’ markets. Factors that may impact the supply of Canadian natural gas transported by ONEOK Partners’ pipelines are primarily the availability of United States supply, Canadian natural gas available for export, Canadian storage capacity, government regulation and demand for Canadian natural gas in Canada and United States consumer markets.

Intrastate and Storage - ONEOK Partners’ intrastate pipelines and storage assets may be impacted by the pace of drilling activity by crude oil and natural gas producers and the decline rate of existing production in the major natural gas production areas in the Mid-Continent region, which include the emerging STACK and SCOOP areas in the Anadarko Basin, the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations, Hugoton Basin and Central Kansas Uplift Basin.

Demand- Demand for services is related directly to ONEOK Partners’ access to supply and the demand for natural gas by the markets that its natural gas pipelines and storage facilities serve. Demand is also affected by weather, the economy, natural gas price volatility and regulatory changes.
Weather - The effect of weather on its natural gas pipelines operations is discussed below under “Seasonality.”
Economy - The strength of the economy directly impacts manufacturing and industrial companies that consume natural gas.
Price volatility - Commodity price volatility can influence producers’ decisions related to the production of natural gas. ONEOK Partners’ pipeline customers, primarily natural gas and electric utilities, require natural gas to operate their businesses and generally are not impacted by location price differentials. However, narrower location price differentials may impact demand for the segment’s services from natural gas marketers as discussed below under “Commodity Prices.”
Regulatory - Demand for this segment’s services is also affected as coal-fired electric generators are retired and replaced with power generation from natural gas. EPA regulations on emissions from coal-fired electric-generation plants, including the Maximum Achievable Control Technology Standards and the Mercury and Air Toxics Standards, have increased the demand for natural gas as a fuel for electric generation, as well as related transportation and storage services. The demand for natural gas and related transportation and storage services is expected to increase over the next several years as these regulations continue to be implemented.

Commodity Prices - As a result of excess supplies of natural gas and the addition of natural gas infrastructure, the natural gas location and seasonal price differentials have remained narrow across the regions where ONEOK Partners operates. Although ONEOK Partners’ revenues are primarily fee-based, commodity prices can affect its results of operations.
Transportation - ONEOK Partners is exposed to market risk through interruptible contracts or when existing firm contracts expire and are subject to renegotiation with customers that have competitive alternatives.
Storage - Natural gas storage revenue is impacted by the differential between forward pricing of natural gas physical contracts and the price of natural gas on the spot market.
Fuel - ONEOK Partners’ fuel costs and the value of the retained fuel in-kind received for its services also are impacted by changes in the price of natural gas.

Seasonality - Demand for natural gas is seasonal. Weather conditions throughout North America may significantly impact regional natural gas supply and demand. High temperatures may increase demand for gas-fired electric generation needed to meet the electricity demand required to cool residential and commercial properties. Cold temperatures may lead to greater demand for ONEOK Partners’ transportation services due to increased demand for natural gas to heat residential and commercial properties. Low precipitation levels may impact the demand for natural gas that is used to fuel irrigation activity in the Mid-Continent region.

To the extent that pipeline capacity is contracted under firm-service transportation agreements, revenue, which is generated primarily from fixed-fee charges, is not significantly impacted by seasonal throughput variations. However, when transportation agreements expire, seasonal demand may affect the value of firm-service transportation capacity.
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Natural gas storage is necessary to balance the relatively steady natural gas supply with the seasonal demand of residential, commercial and electric-generation users. The majority of ONEOK Partners’ storage capacity is either contracted under firm-service agreements or is used for park-and-loan services. ONEOK Partners retains a portion of its storage capacity for operational purposes.

Competition - ONEOK Partners’ natural gas pipelines and storage facilities compete directly with other intrastate and interstate pipeline companies and other storage facilities. Competition among pipelines and natural gas storage facilities is based primarily on fees for services, quality and reliability of services provided, current and forward natural gas prices, proximity to natural gas supply areas and markets, and access to capital. Competition for natural gas transportation services continues to increase as new infrastructure projects are completed and the FERC and state regulatory bodies continue to encourage more competition in the natural gas markets. Regulatory bodies also are encouraging the use of natural gas for electric generation that has traditionally been fueled by coal. The combined cost of coal and the associated rail transportation continues to be competitive with the cost of natural gas; however, the clean-burning aspects of natural gas and abundance of supply make it an economically competitive and environmentally advantaged alternative. We believe that ONEOK Partners’ pipelines and storage assets compete effectively due to their strategic locations connecting supply areas to market centers and other pipelines.

Customers - ONEOK Partners’ natural gas pipeline assets primarily serve local natural gas distribution companies, electric-generation facilities, large industrial companies, municipalities, irrigation customers and marketing companies. Utility customers generally require ONEOK Partners’ services regardless of commodity prices. See discussion regarding ONEOK Partners’ customer credit risk under “Counterparty Credit Risk” in Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Government Regulation - Interstate - ONEOK Partners’Our interstate natural gas pipelines are regulated under the Natural Gas Act, and Natural Gas Policy Act, which givegives the FERC jurisdiction to regulate virtually all aspects of this business, such as transportation of natural gas, rates and charges for services, construction of new facilities, depreciation and amortization policies, acquisition and disposition of facilities, and the initiation and discontinuation of services.


Intrastate - ONEOK Partners’Our intrastate natural gas pipelines in Oklahoma, Kansas and Texas are regulated by the OCC, KCC and RRC, respectively.respectively, and by the FERC under the Natural Gas Policy Act for certain services where we deliver natural gas into FERC regulated natural gas pipelines. While it haswe have flexibility in establishing natural gas transportation rates with customers, there is a maximum rate that itwe can charge itsour customers in Oklahoma and Kansas. In Kansas and for the services regulated by the FERC. In Texas and Kansas, natural gas storage may be regulated by the state and by the FERC for certain types of services. In Oklahoma, natural gas storage isoperations are not subject to rate regulation by the state, and ONEOK Partners haswe have market-based rate authority from the FERC for certain types of services.


See further discussion in the “Regulatory, Environmental and Safety Matters” section.


SEGMENT FINANCIAL INFORMATIONMarket Conditions and Seasonality

We operate primarily fee-based businesses in each of our three reportable segments, and our consolidated earnings were approximately 90% fee-based in 2019. While our Natural Gas Gathering and Processing and Natural Gas Liquids segments generate primarily fee-based earnings, those segments’ results of operations are exposed to volumetric risk. We are exposed to volumetric risk from declining well productivity, reduced drilling activity, severe weather disruptions, operational outages and ethane rejection.

Supply and Demand-Supply for each of our segments depends on crude oil and natural gas drilling and production activities, which are driven by the strength of the economy; the decline rate of existing production; producer access to capital; producer firm commitments to transportation pipelines; natural gas, crude oil and NGL prices; or the demand for each of these products from end users.

Demand for gathering and processing services is dependent on natural gas production by producers in the regions in which we operate. State requirements in North Dakota for producers to reduce natural gas flaring have increased the need for our services to capture, gather and process natural gas. Demand for NGLs and the ability of natural gas processors to successfully and economically sustain their operations affect the volume of unfractionated NGLs produced by natural gas processing plants, thereby affecting the demand for NGL gathering, transportation and fractionation services. Natural gas and NGL products are affected by economic conditions and the demand associated with the various industries that utilize the commodities, such as butanes and natural gasoline used by the refining industry as blending stocks for motor fuel, denaturant for ethanol and diluents for crude oil. Ethane, propane, normal butane and natural gasoline are also used by the petrochemical industry to produce chemical products, such as plastic, rubber and synthetic fibers. Propane is also used to heat homes and businesses. Demand for NGLs is expected to increase at the Mont Belvieu, Texas, NGL market center as new world-scale ethylene production projects, petrochemical plant expansions and NGL export facilities continue to be completed.


Segment Adjusted EBITDA, CustomersCommodity Prices - Our earnings are primarily fee-based in all three of our segments, with limited commodity price risk. In our Natural Gas Gathering and Total Assets - See Note SProcessing segment, we are exposed to commodity price risk as a result of retaining a portion of the Notescommodity sales proceeds associated with our POP with fee contracts. In our Natural Gas Liquids segment, we are exposed to Consolidated Financial Statementscommodity price risk associated with changes in the price of NGLs; the location differential between the Mid-Continent, Chicago, Illinois, and Gulf Coast regions; and the relative price differential between natural gas, NGLs and individual NGL products, which affect our NGL purchases and sales, our exchange services, transportation and storage services, and optimization and marketing financial results. NGL storage revenue may be affected by price volatility and forward pricing of NGL physical contracts versus the price of NGLs on the spot market. In our Natural Gas Pipelines segment, we are exposed to commodity price risk associated with (i) changes in the price of natural gas, which impact our fuel costs and retained fuel in-kind received for our services; and (ii) the differential between forward pricing of natural gas physical contracts and the price of natural gas on the spot market, which affects our natural gas storage revenue.

See additional discussion regarding our commodity price risk and related hedging activities under “Commodity Price Risk” in Part II, Item 7A, Quantitative and Qualitative Disclosures about Market Risk, in this Annual ReportReport.

Seasonality - Cold temperatures usually increase demand for disclosurenatural gas and certain NGL products, such as propane, the main heating fuels for homes and businesses. Warm temperatures usually increase demand for natural gas used in gas-fired electric generation for residential and commercial cooling, as well as agriculture-related equipment like irrigation pumps and crop dryers. Demand for butanes and natural gasoline, which are primarily used by the refining industry as blending stocks for motor fuel, denaturant for ethanol and diluents for crude oil, are also subject to some variability during seasonal periods when certain government restrictions on motor fuel blending products change. During periods of peak demand for a certain commodity, prices for that product typically increase.

Extreme weather conditions, seasonal temperature changes and the impact of temperature and humidity on the mechanical abilities of the processing equipment impact the volumes of natural gas gathered and processed and NGL volumes gathered, transported and fractionated. Power interruptions and inaccessible well sites as a result of severe storms or freeze-offs, a phenomenon where water produced from natural gas freezes at the wellhead or within the gathering system, may cause a temporary interruption in the flow of natural gas and NGLs.

In our Natural Gas Pipelines segment, natural gas storage is necessary to balance the relatively steady natural gas supply with the seasonal demand of residential, commercial and electric-generation users.

Competition- We compete for natural gas and NGL supplywith other midstream companies and major integrated oil companies and independent exploration and production companies that have gathering and processing assets, fractionators, intrastate and interstate pipelines and storage facilities. The factors that typically affect our ability to compete for natural gas and NGL supply are:
quality of services provided;
producer drilling activity;
proceeds remitted and/or fees charged under our contracts;
proximity of our adjusted EBITDAassets to natural gas and totalNGL supply areas and markets;
location of our assets relative to those of our competitors;
efficiency and reliability of our operations;
receipt and delivery capabilities for a discussionnatural gas and NGLs that exist in each pipeline system, plant, fractionator and storage location;
the petrochemical industry’s level of revenuescapacity utilization and feedstock requirements;
current and forward natural gas and NGL prices; and
cost of and access to capital.

We have responded by making capital investments to access and connect new supplies with end-user demand; increasing gathering, processing, fractionation and pipeline capacity; increasing storage, withdrawal and injection capabilities; and reducing operating costs so that we compete effectively. Our competitors also continue to invest in midstream infrastructure to address the growing natural gas and NGL supply and market demand. Our and our competitors’ infrastructure projects may affect commodity prices and compete with and could displace supply volumes from external customers.the Mid-Continent and Rocky Mountain regions and the Permian Basin where our assets are located. We believe our assets are located strategically, connecting diverse supply areas to market centers.

Customers - Our Natural Gas Gathering and Processing and Natural Gas Liquids segments derive services revenue from major and independent crude oil and natural gas producers. Our Natural Gas Liquids segment’s customers also include NGL and

natural gas gathering and processing companies. Our downstream commodity sales customers are primarily utilities, large industrial companies, natural gasoline distributors, propane distributors, municipalities and petrochemical, refining and marketing companies. Our Natural Gas Pipeline segment’s assets primarily serve local natural gas distribution companies, electric-generation facilities, large industrial companies, municipalities, producers, processors and marketing companies. Our utility customers generally require our services regardless of commodity prices. See discussion regarding our customer credit risk under “Counterparty Credit Risk” in Part II, Item 7A, Quantitative and Qualitative Disclosures about Market Risk, in this Annual Report.

Other


Through ONEOK Leasing Company, L.L.C. and ONEOK Parking Company, L.L.C., we own a 17-story office building (ONEOK Plaza) with approximately 505,000517,000 square feet of net rentable space and a parking garage in downtown Tulsa, Oklahoma, where our headquarters are located. ONEOK Leasing Company, L.L.C. leases excess office space to others and operates our headquarters office building. ONEOK Parking Company, L.L.C. owns and operates a parking garage adjacent to our headquarters.


REGULATORY, ENVIRONMENTAL AND SAFETY MATTERS


Environmental Matters -ONEOK Partners isWe are subject to multiplea variety of historical preservation and environmental laws and/or regulations that affect many aspects of itsour present and future operations. Regulated activities include, but are not limited to, those involving air emissions, storm water and wastewater discharges, handling and disposal of solid and hazardous wastes, wetlands and waterways preservation, cultural resources protection, hazardous materials transportation, and pipeline and facility construction. These laws and regulations require ONEOK Partnersus to obtain and/or comply with a wide variety of environmental clearances, registrations, licenses, permits and other approvals. Failure to comply with these laws, regulations, licenses and permits may expose ONEOK Partnersus to fines, penalties and/or interruptions in itsour operations that could be material to our results of operations. For
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example, if a leak or spill of hazardous substances or petroleum products occurs from pipelines or facilities that ONEOK Partners owns, operateswe own, operate or otherwise uses, ONEOK Partnersuse, we could be held jointly and severally liable for all resulting liabilities, including response, investigation and cleanup costs, which could affect materiallyadversely our results of operations and cash flows. In addition, emissions controls and/or other regulatory or permitting mandates under the Clean Air Act and other similar federal and state laws could require unexpected capital expenditures at ONEOK Partners’our facilities. We cannot assure that existing environmental statutes and regulations will not be revised or that new regulations will not be adopted or become applicable to ONEOK Partners.us.

Some scientists have determined that GHG emissions endanger public health and the environment because emissions of such gases may contribute to warming of the earth’s atmosphere and other climatic changes. GHG emissions originate primarily from combustion engine exhaust, heater exhaust and fugitive methane gas emissions. International, federal, regional and/or state legislative and/or regulatory initiatives may attempt to control or limit GHG emissions, including initiatives directed at issues associated with climate change. Various federal and state legislative proposals have been introduced to regulate the emission of GHGs, particularly carbon dioxide and methane, and the United States Supreme Court has ruled that carbon dioxide is a pollutant subject to regulation by the EPA. In addition, there have been international efforts seeking legally binding reductions in emissions of GHGs.

Our environmental actions focus on minimizing the impact of our operations on the environment. These actions include: (i) developing and maintaining an accurate GHG emissions inventory according to current rules issued by the EPA; (ii) improving the efficiency of our various pipelines, natural gas processing facilities and NGL fractionation facilities; (iii) following developing technologies for emissions control and the capture of carbon dioxide to keep it from reaching the atmosphere; and (iv) utilizing practices to reduce the loss of methane from our facilities. In addition, many of our compressor station facilities are designed and operated with electric-driven compression units, which reduce the potential emission from these facilities, including GHG emissions.

We participate in the EPA’s Natural Gas STAR Program to reduce voluntarily methane emissions. We continue to focus on maintaining low methane gas release rates through expanded implementation of best practices to limit the release of natural gas during pipeline and facility maintenance and operations.

We believe it is likely that future governmental legislation and/or regulation may require us either to limit GHG emissions from our operations, to purchase allowances for such emissions or to be subject to a carbon emissions tax. However, we cannot predict precisely what form these future regulations will take, the stringency of the regulations, when they will become effective or the impact on our results of operations. In addition to activities on the federal level, state and regional initiatives could also lead to the regulation of GHG emissions sooner than and/or independent of federal regulation. These regulations could be more stringent than any federal legislation that may be adopted.


For additional information regarding the potential impact of laws and regulations on our operations see Item 1A “Risk Factors.”

Pipeline Safety - ONEOK Partners isWe are subject to PHMSA safety regulations, including pipeline asset integrity-management regulations. The Pipeline Safety Improvement Act of 2002 requires pipeline companies operating high-pressure pipelines to perform integrity assessments on pipeline segments that pass through densely populated areas or near specifically designated high-consequence areas. In January 2012, The Pipeline Safety, Regulatory Certainty and Job Creation Act of 2011 (the 2011 Pipeline Safety Act) was signed into law. The law increased maximum penalties for violating federal pipeline safety regulations, and directs the DOT and Secretary of Transportation to conduct further review or studies on issues that may or may not be material to ONEOK Partners. These issues include, but are not limited to,us and may result in the following:imposition of more stringent regulations.
an evaluation on whether hazardous natural gas liquids and natural gas pipeline integrity-management requirements should be expanded beyond current high-consequence areas;
a review of all natural gas and hazardous natural gas liquids gathering pipeline exemptions;
a verification of records for pipelines in Class 3 and 4 locations and high-consequence areas to confirm maximum allowable operating pressures (MAOP); and
a requirement to test previously untested pipelines operating above 30 percent yield strength in high-consequence areas.


In October 2015, PHMSA issued a noticenotices of proposed rule-making to itsfor hazardous liquid pipeline safety regulations. Among other things, the proposed regulations, would expand the current leak-detection requirements, apply new, more conservative repair criteria and establish timelines for inspecting pipeline facilities potentially affected by an extreme weather event or natural disaster. The proposal would also increase the stringency of integrity management program requirements and set deadlines for the use of internal inspection tools on certain systems. Comments on the proposed rule-making were due by January 2016. PHMSA has issued a prepublication version of the final rule, but it will not be effective until after it is published in the Federal Register. However, in January 2017, prior to publication of the order, the current administration issued a memorandum asking all agencies to immediately withdraw any proposed or final regulations that had been sent to the Office of the Federal Register but not yet published. It is unclear how this will impact the hazardous liquids pipeline safety regulations.

In March 2016, PHMSA issued a notice of proposed rule-making for gas transmission and gathering lines that would substantially revise that agency’s rules for construction, operation and maintenance of natural gas pipeline systems. PHMSA proposes to codify the “traceable, verifiable and complete” standard for records that it issued after a 2010 pipeline explosion in San Bruno, California. Other key changes would modify maximum allowable operating pressure requirements for all gas pipelines, revise several integrity management program requirements, expand the application of several integrity management programs to a newly defined class of “moderate consequence area,” increase corrosion control requirements and modify the regulation of gas gathering lines. Comments on the proposed rule-making were due in July 2016.

In December 2016, PHMSA issued an Interim Final Rule for underground natural gas storage facilities, subjecting these storage facilitiesknown as “the Mega Rule.” Due to minimum federal safety standards forthe large number of rules being considered, PHMSA partitioned the new rulemaking into three sections. To date, the first time. Undersection of rules was finalized and published in 2019 in the Interim Final Rule, existing facilities must have appropriate operational,federal register. These final rules mostly address congressional mandates due to former pipeline safety reauthorizations. Coupled together, these new rules provide increased requirements for operating and maintenance, integrity demonstrationmanagement, public awareness and verification, monitoring, threat and hazard identification, assessment, remediation, site security, emergency response and preparedness, and recordkeeping procedures in place, along with implementation plans and schedules, by January 2018. Comments are due in February 2017.

civil/criminal penalties. The potential capital and operating expenditures related to the referencednew regulations are not fully known, but we do not anticipate a material impact to our planned capital or operations and maintenance costs resulting from compliance with the new or pending regulations. In 2019, legislation was introduced to reauthorize PHMSA through 2024. If passed, requirements for operations and maintenance, integrity management, public awareness, civil and criminal penalties could be increased. The potential capital and operating expenditures related to the proposed regulations are unknown, but we do not anticipate a material impact to ONEOK Partners’our planned capital or operations and maintenance costs resulting from compliance with the current or pending regulations.


Air and Water Emissions- The Clean Air Act, the Clean Water Act, analogous state laws and/or regulations promulgated thereunder impose restrictions and controls regarding the discharge of pollutants into the air and water in the United States. Under the Clean Air Act, a federally enforceable operating permit is required for sources of significant air emissions. ONEOK PartnersWe may be required to incur certain capital expenditures for air pollution-control equipment in connection with obtaining or maintaining permits and approvals for sources of air emissions. The Clean Water Act imposes substantial potential liability for the removal of pollutants discharged to waters of the United States and remediation of waters affected by such discharge.

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International, federal, regional and/or state legislative and/or regulatory initiatives may attempt to control or limit GHG emissions. ONEOK Partners monitorsemissions, including initiatives directed at issues associated with climate change. We monitor all relevant legislation and regulatory initiatives to assess the potential impact on its operations.our operations and otherwise take efforts to limit GHG emissions from our facilities, including methane. The EPA’s Mandatory Greenhouse Gas Reporting Rule requires annual GHG emissions reporting from affected facilities and the carbon dioxide emission equivalents for the natural gas delivered by ONEOK Partnersus and the emission equivalents for all NGLs produced by ONEOK Partnersus as if all of these products were combusted, even if they are used otherwise.


ONEOK Partners’ 2015Our 2018 total emissions reported emissionspursuant to EPA requirements were approximately 47.360 million metric tons of carbon dioxide equivalents. This total includes direct emissions from the combustion of fuel in ONEOK Partners’our equipment, such as compressor engines and heaters, as well as carbon dioxide equivalents from natural gas and NGL products delivered to customers and produced as if all such fuel and NGL products were combusted. The additional cost to gather and report this emission data did not have, and we do not expect it to have, a material impact on our results of operations, financial position or cash flows. In addition, Congress has considered, and may consider in the future, legislation to reduce GHG emissions, including carbon dioxide and methane. Likewise, the EPA may institute additional regulatory rule-making associated with GHG emissions from the oil and natural gas industry. At this time, no rule or legislation has been enacted that assesses any material costs, fees or expenses on any of these emissions.


In June 2013, the Executive Office of the President of the United States (the President) issued the President’s Climate Action Plan, which includes, among other things, plans for further regulatory actions to reduce carbon emissions from various sources. In March 2014, the President released the Climate Action Plan - Strategy to Reduce Methane Emissions (Methane Strategy) that lists a number of actions the federal agencies will undertake to continue to reduce above-ground methane emissions from several industries, including the oilWe monitor proposed and natural gas sectors. The impact of any such regulatory actions on ONEOK Partners’ facilities and operations is unknown. ONEOK Partners continues to monitor these developments and the impact they may have on its businesses.

In September 2015, the EPA published several proposed rule-makings that affect the oil and gas industry. The rule-makings included, but were not limited to, proposed amendments to its existing New Source Performance Standards (NSPS) for the oil and gas industry. The proposed amendments to the NSPS rules included, in part, the proposed direct regulation of methane emissions for the first time as an individual air pollutant from new, modified or reconstructed oil and gas sources, as part of the President’s Methane Strategy. In June 2016, the final NSPS rule was published and became effective in August 2016. The final provisions of the NSPS rule include varied timelines for initial compliance, which run from the effective date. These compliance measures generally include additional capital and operating expenditures. We do not anticipate a material impact to ONEOK Partners’ planned capital, operations or maintenance costs resulting from compliance with the final rule.

In March 2016, the EPA announced a formal information collection request (ICR) process to require companies to provide information to assist in the development of comprehensive regulations to reduce methane emissions from existing oil and gas sources. The EPA published drafts of the ICR on June 3 and September 29 and issued the final ICR on November 10, 2016. The ICR consists of two parts. Part I is designed to obtain information from onshore oil and gas production facilities regarding the number and types of equipment at production facilities. Part 2 will collect detailed information on emissions sources and emissions control devices or practices in use at onshore production, gathering and boosting, processing, compression/transmission, pipeline, natural gas storage, and NGL storage and import/export facilities. ONEOK Partners is in the process of responding to the Part 2 ICR notices it received.

In April 2014, the EPA and the United States Army Corps of Engineers proposed a joint rule-making to redefine the definition of “Waters of the United States” under the Clean Water Act. The final rule was published in June 2015 and became effective on August 28, 2015. Multiple legal actions on the final rule were filed. In October 2015, the Unites States Court of Appeals for the Sixth Circuit entered an order of stay, which is still in effect, and postponed the effect of the final rule nationwide until it decided further proceedings in the case. The final rule is not expected to result in material impacts on ONEOK Partners’ projects, facilities and operations.

In October 2015, the EPA issued a final rule-making to amend downward the National Ambient Air Quality Standards (NAAQS) for ground level ozone. The final rule requires revised designations of the areas in the various states for classification as in attainment or nonattainment for the new ozone NAAQS. Any areas determined to not attain the ozone NAAQS will implicate more strict air permitting requirements for new or modified sources that emit pollutants that contribute to ground level ozone.

rule-makings. At this time, we do not anticipate a material impact to ONEOK Partners’our planned capital, operations and maintenance costs resulting from compliance with the current or pending regulations and EPA actions outlined above.actions. However, the EPA may issue additional regulations, responses, amendments and/or policy guidance, which could alter our present expectations.
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Generally, the EPA rule-makings will require expenditures for updated emissions controls, monitoring and recordkeepingrecord-keeping requirements at affected facilities.


CERCLA - The federal Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), also commonly known as Superfund, imposes strict, joint and several liability, without regard to fault or the legality of the original act, on certain classes of “persons” (defined under CERCLA) who caused and/or contributed to the release of a hazardous substance into the environment. These persons include, but are not limited to, the owner or operator of a facility where the release occurred and/or companies that disposed or arranged for the disposal of the hazardous substances found at the facility. Under CERCLA, these persons may be liable for the costs of cleaning up the hazardous substances released into the environment, damages to natural resources and the costs of certain health studies. We do not expect ONEOK Partners’ responsibilities under CERCLA will have a material impact on our results of operations, financial position or cash flows.

Chemical Site Security-The United States Department of Homeland Security (Homeland Security) released the Chemical Facility Anti-Terrorism Standards in 2007, and the new final rule associated with these regulations was issued in December 2014. ONEOK PartnersWe provided information regarding itsour chemicals via Top-Screens submitted to Homeland Security, and itsour facilities subsequently were assigned one of four risk-based tiers ranging from high (Tier 1) to low (Tier 4) risk, or not tiered at all due to low risk. To date, fourone of itsour facilities havehas been given a Tier 4 rating. Facilities receiving a Tier 4 rating are required to

complete Site Security Plans, andincluding possible physical security enhancements. We do not expect the cost of the Site Security Plans and possible security enhancement costs to have a material impact on our results of operations, financial position or cash flows.


Pipeline Security - The United States Department of Homeland Security’s Transportation Security Administration and the DOT have completed a review and inspection of ONEOK Partners’our “critical facilities” and identified no material security issues. Also, the Transportation Security Administration has released new pipeline security guidelines that include broader definitions for the determination of pipeline “critical facilities.” ONEOK Partners hasWe have reviewed itsour pipeline facilities according to the new guideline requirements, and there have been no material changes required to date.

Environmental Footprint - ONEOK Partners’ environmental and climate change actions focus on minimizing the impact of its operations on the environment. These actions include: (i) developing and maintaining an accurate GHG emissions inventory according to current rules issued by the EPA; (ii) improving the efficiency of its various pipelines, natural gas processing facilities and natural gas liquids fractionation facilities; (iii) following developing technologies for emissions control and the capture of carbon dioxide to keep it from reaching the atmosphere; and (iv) utilizing practices to reduce the loss of methane from its facilities.

ONEOK Partners participates in the EPA’s Natural Gas STAR Program to reduce voluntarily methane emissions. ONEOK Partners continues to focus on maintaining low rates of lost-and-unaccounted-for methane gas through expanded implementation of best practices to limit the release of natural gas during pipeline and facility maintenance and operations.


EMPLOYEES


At January 31, 2017,2020, we employed 2,3842,882 people.



INFORMATION ABOUT OUR EXECUTIVE OFFICERS


All executive officers are elected annually by our Board of Directors. Our executive officers listed below include the officers who have been designated by our Board of Directors as our Section 16 executive officers.
Name and Position Age Business Experience in Past Five Years
John W. Gibson 6467

 20142011 to present Chairman of the Board, ONEOK and ONEOK Partners
Chairman of the Board   20112007 to 20142017 Chairman and Chief Executive Officer, ONEOK andof the Board, ONEOK Partners
Terry K. Spencer 5760

 2014 to present President and Chief Executive Officer, ONEOK and ONEOK Partners
President and Chief Executive Officer2014 to 2017President and Chief Executive Officer, ONEOK Partners
   2014 to present Member of the Board of Directors, ONEOK and ONEOK Partners
    20122014 to 20142017 President, ONEOK andMember of the Board of Directors, ONEOK Partners
Robert F. Martinovich 5962

 2015 to present Executive Vice President and Chief Administrative Officer, ONEOK and ONEOK Partners
Executive Vice President and Chief Administrative Officer2015 to 2017Executive Vice President and Chief Administrative Officer, ONEOK Partners
   2014 to 2015 Executive Vice President, Commercial, ONEOK and ONEOK Partners
Walter S. Hulse III56
2019 to presentChief Financial Officer, Treasurer and Executive Vice President, Strategic Planning and Corporate Affairs, ONEOK
Chief Financial Officer, Treasurer and Executive Vice President, Strategic Planning and Corporate Affairs   20132017 to 20142019 Chief Financial Officer and Executive Vice President, Operations,Strategic Planning and Corporate Affairs, ONEOK and ONEOK Partners
    2012Executive Vice President, Chief Financial Officer and Treasurer, ONEOK and ONEOK Partners
2011 to 2012Member of the Board of Directors, ONEOK Partners
Walter S. Hulse III53
2015 to present2017 Executive Vice President, Strategic Planning and Corporate Affairs, ONEOK and ONEOK Partners
Executive Vice President, Strategic Planning and Corporate Affairs   2012 to 2015 Managing Member, Spinnaker Strategic Advisory Services, LLC
Wesley J. ChristensenKevin L. Burdick 6355

 20142017 to presentExecutive Vice President and Chief Operating Officer, ONEOK
Executive Vice President and Chief Operating Officer2017Executive Vice President and Chief Commercial Officer, ONEOK and ONEOK Partners
2016 to 2017Senior Vice President, Natural Gas Gathering and Processing, ONEOK Partners
2013 to 2016Vice President, Natural Gas Gathering and Processing, ONEOK Partners
Charles M. Kelley61
2018 to present Senior Vice President, Operations,Natural Gas, ONEOK
Senior Vice President, Natural Gas2017 to 2018Senior Vice President, Natural Gas Gathering & Processing, ONEOK
2015 to 2017Senior Vice President, Corporate Planning and Development, ONEOK and ONEOK Partners
Senior Vice President, Operations   20112014 to 20142015Vice President, Corporate Development, ONEOK and ONEOK Partners
Sheridan C. Swords50
2017 to present Senior Vice President, Operations,Natural Gas Liquids, ONEOK
Senior Vice President, Natural Gas Liquids2013 to 2017Senior Vice President, Natural Gas Liquids, ONEOK Partners
Stephen W. LakeB. Allen 5346

 20122017 to present Senior Vice President, General Counsel and Assistant Secretary, ONEOK and ONEOK Partners
Senior Vice President, General Counsel
and Assistant Secretary
   
Derek S. Reiners2008 to 2017 45
2013 to presentSenior Vice President Chief Financial Officer and Treasurer,Associate General Counsel, ONEOK and ONEOK Partners
Senior Vice President, Chief Financial Officer and
Treasurer
Mary M. Spears
 40
 2009 to 2012Senior Vice President and Chief Accounting Officer, ONEOK and ONEOK Partners
Sheppard F. Miers III48
20132019 to present Vice President and Chief Accounting Officer, ONEOK and ONEOK Partners
Vice President and Chief Accounting Officer   20092015 to 20122019 Vice President and Controller,Director, SEC Reporting, ONEOK
2015 to 2017Director, SEC Reporting, ONEOK Partners
2009 to 2015Director, Natural Gas Liquids Accounting, ONEOK Partners


No family relationships exist between any of the executive officers, nor is there any arrangement or understanding between any executive officer and any other person pursuant to which the officer was selected.


INFORMATION AVAILABLE ON OUR WEBSITE


We make available, free of charge, on our website (www.oneok.com) copies of our Annual Reports, Quarterly Reports, Current Reports on Form 8-K, amendments to those reports filed or furnished to the SEC pursuant to Section 13(a) or 15(d) of the Exchange Act and reports of holdings of our securities filed by our officers and directors under Section 16 of the Exchange Act

as soon as reasonably practicable after filing such material electronically or otherwise furnishing it to the SEC. Copies of our Code of Business Conduct and Ethics, Corporate Governance Guidelines, Director Independence Guidelines, Corporate Sustainability Report, Bylaws and the written charter of our Audit Committee also are available on our website, and we will provide copies of these documents upon request. Our

In addition to our filings with the SEC and materials posted on our website, we also use social media platforms as additional channels of distribution to reach public investors. Information contained on our website, posted on our social media accounts, and any contents thereofcorresponding applications, are not incorporated by reference into this report.

We also make available on our website the Interactive Data Files required to be submitted and posted pursuant to Rule 405 of Regulation S-T.


ITEM 1A.    RISK FACTORS


Our investors should consider the following risks that could affect us and our business. Although we have tried to identify key factors, our investors need to be aware that other risks may prove to be important in the future. New risks may emerge at any time, and we cannot predict such risks or estimate the extent to which they may affect our financial performance. Risks related to ONEOK Partners’ business discussed below will also affect us indirectly as we are the sole general partner and, as of December 31, 2016, owned 41.2 percent of ONEOK Partners. Investors should consider carefully consider the following discussion of risks and the other information included or incorporated by reference in this Annual Report, including “Forward-Looking Statements,” which are included in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations.


TableIf the level of contentsdrilling in the regions in which we operate declines substantially near our assets, our volumes and revenues could decline.

Our gathering and transportation pipeline systems are dependent upon production from natural gas and crude oil wells, which naturally declines over time. As a result, our cash flows associated with these wells will also decline over time. In order to maintain or increase throughput levels on our gathering and transportation pipeline systems and the asset utilization rates at our processing and fractionation facilities, we must continually obtain new supplies. Our ability to maintain or expand our businesses depends largely on the level of drilling and production by third parties in the regions in which we operate. Our natural gas and NGL supply volumes may be impacted if producers curtail or redirect drilling and production activities. Drilling and production are impacted by factors beyond our control, including:
demand and prices for natural gas, NGLs and crude oil;
producers’ access to capital;
producers’ finding and development costs of reserves;
producers’ ability to obtain necessary permits, drilling rights and surface access in a timely manner and on reasonable terms;
natural gas field characteristics and production performance; and
capacity constraints on natural gas, crude oil and NGL infrastructure from the producing areas and our facilities.

Commodity prices have experienced significant volatility. Drilling and production activity levels may vary across our geographic areas; however, a prolonged period of low commodity prices may reduce drilling and production activities across all areas. If we are not able to obtain new supplies to replace the natural decline in volumes from existing wells or because of competition, throughput on our gathering and transportation pipeline systems and the utilization rates of our processing and fractionation facilities would decline, which could affect adversely our business, results of operations, financial position and cash flows, and our ability to pay cash dividends.

Continued development of supply sources outside of our operating regions could impact demand for our services.

Natural gas production areas outside of our operating regions may compete with natural gas originating in production areas connected to our systems. For example, increased production in the Marcellus Shale may cause natural gas and NGLs in supply areas connected to our systems to be diverted to markets other than our traditional market areas and may affect capacity utilization adversely on our pipeline systems and our ability to renew or replace existing contracts. In our Natural Gas Gathering and Processing segment, the development of reserves could move drilling rigs from our current service areas to other areas, which may reduce demand for our services. In our Natural Gas Pipelines segment, the displacement of natural gas originating in supply areas connected to our pipeline systems by supply sources that are closer to the end-use markets could reduce demand for our services. Either of these possibilities could result in lower revenues, which could affect adversely our business, results of operations, financial position and cash flows.


RISKS RELATED TO THE MERGER TRANSACTION

The Merger Transaction isOur operations are subject to conditionsoperational hazards and unforeseen interruptions, which could affect adversely our business and for which we may not be consummated even if the required ONEOK shareholder and ONEOK Partners unitholder approvalsadequately insured.

Our operations are obtained.

The Merger Transaction is subject to the satisfaction or waiver of certain conditions, including approvalall of the Merger Agreement by ONEOK Partners’ unitholdersrisks and approval of the issuance of ONEOK common stock in connectionhazards typically associated with the Merger Transaction by ONEOK shareholders, someoperation of which are out of the control of ONEOKnatural gas and ONEOK Partners. The Merger Agreement contains other conditions that, if not satisfied or waived, would result in the Merger Transaction not occurring, even though the ONEOK shareholdersNGL gathering, transportation and the ONEOK Partners unitholders may have voted in favor of the Merger Transaction-related proposals presented to them. Satisfaction of some of these other conditions to the Merger Transaction is not entirely in the control of ONEOK or ONEOK Partners. In addition, ONEOKdistribution pipelines, storage facilities and ONEOK Partners can agree not to consummate the Merger Transaction even if all shareholderprocessing and unitholder approvals have been received. The closing conditions to the Merger Transaction may not be satisfied, and ONEOK and ONEOK Partners may choose not to, or may be unable to, waive an unsatisfied condition,fractionation facilities, which may cause the Merger Transaction not to occur.

The Merger Agreement contains certain termination rights for both ONEOK and ONEOK Partners, including, among others, (i) by ONEOK or ONEOK Partners, if the Merger Transaction is not consummated by September 30, 2017, (ii) by ONEOK, if the Board of Directors or the conflicts committee of ONEOK Partners GP takes certain actions with respect to its recommendation of the Merger prior to the ONEOK Partners’ unitholder meeting, and (iii) by ONEOK Partners, if a special committee of the ONEOK Board of Directors takes certain actions with respect to its recommendation of the issuance of ONEOK common stock in connection with the Merger Transaction prior to the ONEOK shareholder meeting. In the event of termination of the Merger Agreement under certain circumstances, we may be required to pay ONEOK Partners a termination fee in the form of a temporary reduction in incentive distributions (up to, in certain instances, $300 million) and, under other certain circumstances, ONEOK Partners may be required to pay us a termination fee (up to, in certain instances, $300 million in cash).

We and ONEOK Partners may incur substantial transaction-related costs in connection with the Merger Transaction.

We and ONEOK Partners expect to incur nonrecurring transaction-related costs associated with completing the Merger Transaction. Nonrecurring transaction costs include, but are not limited to, fees paidleaks, pipeline ruptures, the breakdown or failure of equipment or processes and the performance of facilities below expected levels of capacity and efficiency. Other operational hazards and unforeseen interruptions include adverse weather conditions, accidents, explosions, fires, the collision of equipment with our pipeline facilities (for example, this may occur if a third party were to legal, financialperform excavation or construction work near our facilities) and accounting advisors, filing fees, proxy solicitation costscatastrophic events such as tornados, hurricanes, earthquakes, floods, and printing costs.

Failure to complete, or significant delays in completing,other similar events beyond our control. Also, the Merger TransactionUnited States government warned that energy assets, specifically the nation’s pipeline infrastructure, may be targets of terrorist attacks. An act of terrorism could negatively affect the trading pricetarget our facilities, those of our common stocksuppliers or customers or those of other pipelines. A casualty occurrence may result in injury or loss of life, extensive property damage or environmental damage. Liabilities incurred and our future business and financial results.

Completion ofinterruptions to the Merger Transaction is not assured and is subject to risks, including the risks that approval of the Merger Transaction by our shareholders or by any applicable governmental agencies or third parties is not obtained or that other closing conditions are not satisfied. If the Merger Transaction is not completed, or if there are significant delays in completing the Merger Transaction, the trading priceoperations of our common stockpipeline or other facilities caused by such an event could reduce our revenues and our future business and financial results could be negatively affected, and we will be subject to several risks, including the following:
we and ONEOK Partners may be liable for damages to one another under the terms and conditions of the Merger Agreement;
negative reactions from the financial markets, including declines in the price of our common stock due to the fact that the current price may reflect a market assumption that the Merger Transaction will be completed;
having to pay certain significant costs relating to the Merger Transaction; and
the attention of management may have been diverted to the Merger Transaction rather than its own operations and pursuit of other opportunities that could have been beneficial to ONEOK.

We may not realize the benefits we expect from the Merger Transaction.

We believe that the Merger Transaction will, among other things, provide increased financial flexibility for execution of our strategic growth plan. However, our assessments and expectations regarding the anticipated benefits of the Merger Transaction may prove to be incorrect. Accordingly, there can be no assurance we will realize the anticipated benefits of the Merger Transaction.


We are subject to provisions that limitincrease expenses, thereby impairing our ability to pursue alternativesmeet our obligations. Insurance proceeds may not be adequate to the Merger Transactioncover all liabilities or expenses incurred or revenues lost, and could discourage a potential acquirer of ours that does not want the Merger Transaction completed from making a favorable alternative transaction proposal.

Under the Merger Agreement, we are restricted from soliciting any proposal for, or initiating discussions regarding, any acquisition transaction regarding ONEOK that is reasonably likely to impede or delay the closing of the Merger Transaction. Unless and until the Merger Agreement is terminated, subject to specified exceptions, we are restricted from, among other things, soliciting, initiating, knowingly facilitating, knowingly encouraging or knowingly inducing, any inquiry, proposal or offer for an acquisition proposal for ONEOK that is reasonably likely to impede or delay the closing of the Merger Transaction. These and other provisions in the Merger Agreement could discourage a third party that may have an interest in acquiringnot fully insured against all or a significant part of ONEOK from considering or proposing that acquisition.

RISKS INHERENT IN ONEOK’S BUSINESS

Our cash flow depends heavily on the earnings and distributions of ONEOK Partners.

Our partnership interest in ONEOK Partners is our primary cash-generating source. Therefore, our cash flow is heavily dependent upon the ability of ONEOK Partners to make cash distributions to its partners. A significant decline in ONEOK Partners’ earnings and/or cash distributions could have a corresponding negative impact on us. For information on the risk factorsrisks inherent in the business of ONEOK Partners, see the section below entitled “Additional Risk Factors Related to ONEOK Partners’ Business” and Item 1A, Risk Factors in the ONEOK Partners’ Annual Report.

Our indebtedness could impair our financial condition and our ability to fulfill our obligations.

As of December 31, 2016, we had total indebtedness of approximately $1.6 billion, which excludes the debt of ONEOK Partners. Our indebtedness could have significant consequences. For example, it could:
make it more difficult for us to satisfy our obligations with respect to our senior notes and our other indebtedness due to the increased debt-service obligations, which could, in turn, result in an event of default on such other indebtedness or our senior notes;business.
impair our ability to obtain additional financing in the future for working capital, capital expenditures, acquisitions or general business purposes;
diminish our ability to withstand a downturn in our business or the economy;
require us to dedicate a substantial portion of our cash flow from operations to debt-service payments, reducing the availability of cash for working capital, capital expenditures, acquisitions, dividends or general corporate purposes;
limit our flexibility in planning for, or reacting to, changes in our business and the industry in which ONEOK Partners operates; and
place us at a competitive disadvantage compared with our competitors that have proportionately less debt.

We are not prohibited under the indentures governing our senior notes from incurring additional indebtedness, but our debt agreements do subject us to certain operational limitations summarized in the next paragraph. If we incur significant additional indebtedness, it could worsen the negative consequences mentioned above and could affect adversely our ability to repay our other indebtedness.

Our revolving debt agreements with banks contain provisions that restrict our ability to finance future operations or capital needs or to expand or pursue our business activities. For example, certain of these agreements contain provisions that, among other things, limit our ability to make loans or investments, make material changes to the nature of our business, merge, consolidate or engage in asset sales, grant liens or make negative pledges. Certain agreements also require us to maintain certain financial ratios, which limit the amount of additional indebtedness we can incur, as described in the “Liquidity and Capital Resources” section of Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operation. These restrictions could result in higher costs of borrowing and impair our ability to generate additional cash. Future financing agreements we may enter into may contain similar or more restrictive covenants.

If we are unable to meet our debt-service obligations, we could be forced to restructure or refinance our indebtedness, seek additional equity capital or sell assets. We may be unable to obtain financing or sell assets on satisfactory terms, or at all.


Federal, state and local jurisdictions may challenge our tax return positions.

The positions taken in our federal and state tax return filings require significant judgments, use of estimates and the interpretation and application of complex tax laws. Significant judgment is also required in assessing the timing and amounts of deductible and taxable items. Despite management’s belief that our tax return positions are fully supportable, certain positions may be successfully challenged by federal, state and local jurisdictions.

The separation of ONE Gas could result in substantial tax liability.

We have received a private letter ruling from the IRS substantially to the effect that, for U.S. federal income tax purposes, the separation and certain related transactions qualify under Sections 355 and/or 368 of the U.S. Internal Revenue Code of 1986, as amended. If the factual assumptions or representations made in the request for the private letter ruling prove to have been inaccurate or incomplete in any material respect, then we will not be able to rely on the ruling. Furthermore, the IRS does not rule on whether a distribution such as the separation satisfies certain requirements necessary to obtain tax-free treatment under section 355 of the Code. The private letter ruling was based on representations by us that those requirements were satisfied, and any inaccuracy in those representations could invalidate the ruling. In connection with the separation, we obtained an opinion of outside legal and tax counsel, substantially to the effect that, for U.S. federal income tax purposes, the separation and certain related transactions qualify under Sections 355 and 368 of the Code. The opinion relies on, among other things, the continuing validity of the private letter ruling and various assumptions and representations as to factual matters made by us which, if inaccurate or incomplete in any material respect, would jeopardize the conclusions reached by such counsel in its opinion. The opinion will not be binding on the IRS or the courts, and there can be no assurance that the IRS or the courts would not challenge the conclusions stated in the opinion or that any such challenge would not prevail.

We have a holding company structure in which our subsidiaries conduct our operations and own our operating assets.

We are a holding company, and our subsidiaries conduct all of our operations and own all of our operating assets. We do not have significant assets other than our interests in ONEOK Partners and the equity in our subsidiaries. As a result our ability to pay dividends to our shareholdersof market conditions, premiums and to service our debt depends on the performancedeductibles for certain insurance policies can increase substantially, and, in some instances, certain insurance may become unavailable or available only for reduced amounts of our subsidiaries and their ability to distribute funds to us. The ability of our subsidiaries to make distributions to us may be restricted by, among other things, partnership agreements, credit facilities, applicable state partnership laws and other laws and regulations. If we are unable to obtain funds from our subsidiaries,coverage. Consequently, we may not be able to pay dividends to our shareholdersrenew existing insurance policies or to pay interest or principalpurchase other desirable insurance on our debt when due.

Although we control ONEOK Partners, we may have conflicts of interest with ONEOK Partners that could subject us to claims that we have breached our fiduciary duty to ONEOK Partners and its unitholders.

We are the sole general partner and owned 41.2 percent of ONEOK Partners as of December 31, 2016. Conflicts of interest may arise between us and ONEOK Partners and its unitholders. In resolving these conflicts, we may favor our own interests and the interests of our affiliates over the interests of ONEOK Partners and its unitholders as long as the resolution does not conflict with the Partnership Agreement or our fiduciary duties to ONEOK Partners and its unitholders.

commercially reasonable terms, if at all. If we are not fully reimbursed or indemnified for obligations and liabilities wewere to incur in managing the business and affairs of ONEOK Partners, the value of our shares could decline.

In our capacity as the general partner of ONEOK Partners, we may make expenditures on ONEOK Partners’ behalfa significant liability for which we will seek reimbursement from ONEOK Partners. In addition, under Delaware partnership law, we have, in our capacity as ONEOK Partners’ general partner, unlimited liability for the obligations of ONEOK Partners, such as ONEOK Partners’ debts and environmental liabilities, except for those contractual obligations of ONEOK Partners that are expressly made without recourse to the general partner and as limited by the Partnership Agreement. To the extent we incur obligations on behalf of ONEOK Partners, we are entitled to be reimbursed or indemnified by ONEOK Partners. If ONEOK Partners is unable or unwilling to reimburse or indemnify us, we may be unable to satisfy these liabilities or obligations, which would likely reduce the value of our shares.

ONEOK Partners’ unitholders have the right to remove us as their general partner with the approval of the holders of 66 2/3 percent of all units, excluding the units held by us, which would cause us to lose our general partner interest and incentive distribution rights in OKS and the ability to manage them.

We currently manage ONEOK Partners through our ownership of its general partner interest. The Partnership Agreement gives common unitholders of ONEOK Partners the right to remove the general partner of ONEOK Partners upon the affirmative vote

of holders of 66 2/3 percent of ONEOK Partners’ outstanding units, excluding the units held by the general partner and its affiliates. If we were removed as general partner of ONEOK Partners, we would receive cash or common units in exchange for our 2.0 percent general partner interest and incentive distribution rights, and our Class B units would have the right to share in Partnership quarterly cash distributions based on 123.5 percent of the amount of any Partnership cash distribution, but we would lose the ability to manage ONEOK Partners. Although the common units or cash we would receive are intended under the terms of the Partnership Agreement tonot fully compensate us in the event such an exchange is required, the value of these common units or investments we make with the cash over time may not be equivalent to the value of the general partner interest and the incentive distribution rights had we retained them.

A reduction in ONEOK Partners’ cash distributions would disproportionately affect the amount of cash distributions to which we are entitled.

Through our ownership of the incentive distribution rights in ONEOK Partners, we are entitled to receive our pro rata share of specified percentages of total cash distributions made by ONEOK Partners asinsured, it reaches established target cash distribution levels as specified in the the Partnership Agreement. We currently receive a portion of our pro rata share of cash distributions from ONEOK Partners based on the highest incremental percentage, 50 percent, to which we are entitled pursuant to our incentive distribution rights in ONEOK Partners. As a result, any reduction in quarterly cash distributions from ONEOK Partners would have the effect of disproportionately reducing the amount of all cash distributions that we receive from ONEOK Partners based on our ownership interest in the incentive distribution rights in ONEOK Partners as compared to cash distributions we receive on our General Partner interest in ONEOK Partners and our ONEOK Partners common units.

Cash distributions on our incentive distribution rights in ONEOK Partners are more uncertain than cash distributions on the common and Class B units we hold.

Our ownership of the incentive distribution rights in ONEOK Partners entitles us to receive our pro rata share of specified percentages of total cash distributions made by ONEOK Partners with respect to any particular quarter only in the event that ONEOK partners distributes more than $0.3025 per unit for such quarter. As a result, the holders of ONEOK Partners’ common and Class B units have a priority over the holders of ONEOK Partners’ incentive distribution rights to the extent of cash distributions by ONEOK Partners up to and including $0.3025 per unit for any quarter. This priority results in greater certainty of common unitholders and Class B unitholders receiving distributions, when compared to holders of incentive distribution rights.

ONEOK Partners may issue additional units, which may increase the risk that ONEOK Partners will not have sufficient available cash to maintain or increase its per unit cash distribution level.

ONEOK Partners may issue additional units, including units that rank senior to the ONEOK Partners’ common units, Class B units and the incentive distribution rights as to quarterly cash distributions. The payment of cash distributions on those additional units may increase the risk that ONEOK Partners may not have sufficient cash available to maintain or increase its per unit distribution level, which in turn may impact the available cash that we receive from ONEOK Partners to pay dividends. To the extent these units are senior to the common units, Class B units or the incentive distribution rights, there is an increased risk that we will not receive the same level or increased cash distributions on the common units, Class B units and incentive distribution rights we own. Neither the common units, Class B units nor the incentive distribution rights are entitled to any arrearages from prior quarters.

Our ability to sell our partnership interests in ONEOK Partners may be limited by securities law restrictions and liquidity constraints.

All of the approximately 41.3 million common units and approximately 73.0 million Class B units of ONEOK Partners that we own are either unregistered, restricted or control securities or registered control securities within the meaning of Rule 144 under the Securities Act, and thus cannot be sold by us without registration or an applicable exemption from registration. Pursuant to the terms of the Partnership Agreement, we only have registration rights with respect to such ONEOK Partners common units and Class B units if Rule 144 of the Securities Act (or any successor rule or regulation to Rule 144) or another exemption from registration is not available to enable us to dispose of such ONEOK Partners common units or Class B units at the time we desire to do so without registration under the Securities Act. Due to the foregoing limitation, we are primarily limited to sales pursuant to Rule 144, which limits selling into the market in any three-month period to an amount of ONEOK Partners’ common and/or Class B units that does not exceed the greater of 1 percent of the total number of ONEOK Partners’ common units outstanding or the average weekly reported trading volume of ONEOK Partners’ common units for the four calendar weeks prior to the sale. In addition, we face contractual limitations on our ability to sell our general partner interest and incentive distribution rights, and the market for such interests is illiquid.


Holders of our common stock may not receive dividends in the amount identified in guidance, or any dividends at all.

We may not have sufficient cash each quarter to pay dividends or maintain current or expected levels of dividends. The actual amount of cash we pay in the form of dividends may fluctuate from quarter to quarter and will depend on various factors, some of which are beyond our control, including the amount of cash that ONEOK Partners distributes to us, our working capital needs, our ability to borrow, the restrictions contained in our indentures and credit facility, our debt service requirements and the cost of acquisitions, if any. A failure either to pay dividends or to pay dividends at expected levels could result in a loss of investor confidence, reputational damage and a decrease in the value of our stock price.

The cost of providing pension and postretirement health care benefits to eligible employees and qualified retirees is subject to changes in pension fund values and changing demographics and may increase.

We have a defined benefit pension plan for certain employees and postretirement welfare plans that provide postretirement medical and life insurance benefits to certain employees who retire with at least five years of service. The cost of providing these benefits to eligible current and former employees is subject to changes in the market value of our pension and postretirement benefit plan assets, changing demographics, including longer life expectancy of plan participants and their beneficiaries and changes in health care costs. For further discussion of our defined benefit pension plan, see Note L of the Notes to Consolidated Financial Statements in this Annual Report.

Any sustained declines in equity markets and reductions in bond yields may have a material adverse effect on the value of our pension and postretirement benefit plan assets. In these circumstances, additional cash contributions to our pension plans may be required, which could aversely impact our business, financial condition and liquidity.

RISKS INHERENT IN BOTH ONEOK AND ONEOK PARTNERS

Market volatility and capital availability could affect adversely our business.

The capitalbusiness, results of operations, financial position and global credit markets have experienced volatilitycash flows. Further, the proceeds of any such insurance may not be paid in a timely manner and disruption in the past. In many cases during these periods, the capital markets have exerted downward pressure on equity values and reduced the credit capacity for certain companies. Much of ONEOK Partners’ business is capital intensive, and its ability to grow is dependent, in part, upon our and ONEOK Partners’ ability to access capital at rates and on terms we determine to be attractive. Similar or more severe levels of global market disruption and volatility may have an adverse effect on us or ONEOK Partners resulting from, but not limited to, disruption of access to capital and credit markets, difficulty in obtaining financing necessary to expand facilities or acquire assets, increased financing costs and increasingly restrictive covenants. If we or ONEOK Partners’ are unable to access capital at competitive rates, ONEOK Partners’ strategy of enhancing the earnings potential of its existing assets, including through capital-growth projects and acquisitions of complementary assets or businesses, may be affected adversely. A number of factors could affect adversely our and ONEOK Partners’ abilityinsufficient if such an event were to access capital, including: (i) general economic conditions; (ii) capital market conditions; (iii) market prices for natural gas, NGLs and other hydrocarbons; (iv) the overall health of the energy and related industries; (v) ability to maintain investment-grade credit ratings; (vi) unit price and (vii) capital structure. If our and ONEOK Partners’ ability to access capital becomes constrained significantly, our and ONEOK Partners’ interest costs and cost of equity will likely increase and could affect adversely our financial condition and future results of operations.occur.


Our operating results may be affected materially and adversely by unfavorable economic and market conditions.


EconomicAn adverse change in economic conditions worldwide have from time to time contributed to slowdownsor in the economic regions in which we operate could negatively affect the crude oil and natural gas industry, as well as in the specific segments and markets in which ONEOK Partners operates,we operate, resulting in reduced demand and increased price competition for its productsour services and services. ONEOK Partners’products. Our operating results in one or more geographic regions may also be affected by uncertain or changing economic conditions within that region. Volatility in commodity prices may have an impact on many of ONEOK Partners’our suppliers and customers, which, in turn, could have a negative impact on their ability to meet their obligations to ONEOK Partners.us. Periods of severe volatility in equity and credit markets may disrupt our access to such markets, make it difficult to obtain financing necessary to expand facilities or acquire assets, increase financing costs and result in the imposition of restrictive financial covenants. If adverse global or regional economic and market conditions (including volatility in commodity markets) or economic conditions in the United States or other key markets remain uncertain or persist, spread or deteriorate further, we and ONEOK Partners may experience material impacts on our businesses, financial condition,business, results of operations, financial position, cash flows and liquidity.


Terrorist attacks directed atIncreased regulation of exploration and production activities, including hydraulic fracturing, well setbacks and disposal of waste water, could result in reductions or delays in drilling and completing new crude oil and natural gas wells.

The crude oil and natural gas industry is relying increasingly on supplies from nonconventional sources, such as shale and tight sands. Natural gas extracted from these sources frequently requires hydraulic fracturing, which involves the pressurized injection of water, sand and chemicals into a geologic formation to stimulate crude oil and natural gas production. Legislation or regulations placing restrictions on exploration and production activities, including hydraulic fracturing and disposal of waste water, could result in operational delays, increase operating costs and additional regulatory burdens on exploration and production operators. Any of these factors could reduce their production of unprocessed natural gas and, in turn, affect adversely our revenues and results of operations by decreasing the volumes of natural gas and NGLs gathered, treated, processed, fractionated and transported on our or ONEOK Partners’ facilitiesour joint ventures’ assets.

In the competition for supply, we may have significant levels of excess capacity on our natural gas and NGL pipelines, processing, fractionation and storage assets.

Our natural gas and NGL pipelines, processing, fractionation and storage assets compete with other pipelines, processing, fractionation and storage assets for natural gas and NGL supply delivered to the markets we serve. As a result of competition, we may have significant levels of uncontracted or discounted capacity on our assets, which could affect adversely our business.business, results of operations, financial position and cash flows.


The United States government has issued warnings that energy assets, specifically the nation’s pipeline infrastructure, may be future targets of terrorist organizations. These developments may subject ONEOK Partners’ operationsGrowing our business by constructing new pipelines and facilities or making modifications to increased risks. Any

future terrorist attack that targets ONEOK Partners’our existing facilities those of its customerssubjects us to construction risk and in some cases, those of other pipelines, or our facilities could have a material adverse effect on our business.

Our businesses are subject to market and credit risks.

We and ONEOK Partners are exposed to market and creditsupply risks, in all of our operations. To reduce the impact of commodity price fluctuations, ONEOK Partners uses derivative transactions, such as swaps, futures and forwards, to hedge anticipated purchases and sales ofshould adequate natural gas NGLsor NGL supply be unavailable upon completion of the facilities.

To expand our business, we regularly construct new and crude oilmodify or expand existing pipelines and firm transportation commitments. Interest-rate swaps are also used to manage interest-rate risk. However, derivative instruments do not eliminate the risks. Specifically, such risks include commodity price changes, market supply shortages, interest-rate changesgathering, processing, storage and counterparty default.fractionation facilities. The impactconstruction and modification of these variables could resultfacilities may involve the following risks:
projects may require significant capital expenditures, which may exceed our estimates, and involve numerous regulatory, environmental, political, legal and weather-related uncertainties;
projects may increase demand for labor, materials and rights of way, which may, in turn, affect our costs and ONEOK Partners’ inability to fulfill contractual obligations, significantly higher energy or fuel costs relative to corresponding sales contracts, or increased interest expense.schedule;

We or ONEOK Partners may not be able to make additional strategic acquisitions or investments.

Our and ONEOK Partners’ ability to make strategic acquisitions and investments will depend on:
the extent to which acquisitions and investment opportunities become available;
success in bidding for the opportunities that do become available;
regulatory approval, if required, of the acquisitions or investments on favorable terms; and
access to capital, including the ability to use our or equity in acquisitions or investments, and the terms upon which we obtain capital.

If we or ONEOK Partners are unable to make strategic investments and acquisitions, we or ONEOK Partners may be unable to grow.obtain new rights of way to connect new natural gas or NGL supplies to our existing gathering or transportation pipelines;

Acquisitions that appear to be accretive may nevertheless reduce our cash from operations on a per-share basis.

Any acquisition involves potential risks that may include, among other things:
inaccurate assumptions about volumes, revenues and costs, including potential synergies;
an inability to integrate successfully the businesses we acquire;
decrease in our liquidity as a result of our using a significant portion of our available cash or borrowing capacity to finance the acquisition;
a significant increase in our interest expense and/or financial leverage if we incur additional debt to finance the acquisition;
the assumption of unknown liabilities for which we are not indemnified, our indemnity is inadequate or our insurance policies may exclude from coverage;
an inability to hire, train or retain qualified personnel to manage and operate the acquired business and assets;
limitations on rights to indemnity from the seller;
inaccurate assumptions about the overall costs of equity or debt;
the diversion of management’s and employees’ attention from other business concerns;
unforeseen difficulties operating in new product areas or new geographic areas; 
increased regulatory burdens;
customer or key employee losses at an acquired business; and
increased regulatory requirements.

If we or ONEOK Partners consummate any future acquisitions, our capitalization and results of operations may change significantly, and investors will not have the opportunity to evaluate the economic, financial and other relevant information that we will consider in determining the application of our resources to future acquisitions.

Our and ONEOK Partners’ established risk-management policies and procedures may not be effective, and employees may violate our risk-management policies.

We have developed and implemented a comprehensive set of policies and procedures that involve both our senior management and the Audit Committee of our Board of Directors to assist us in managing risks associated with, among other things, the marketing, trading and risk-management activities associated with our business segments. Our risk policies and procedures are intended to align strategies, processes, people, information technology and business knowledge so that risk is managed throughout the organization. As conditions change and become more complex, current risk measures may fail to adequately assess the relevant risk due to changes in the market and the presence of risks previously unknown to us. Additionally, if

employees fail to adhere to our policies and procedures or if our policies and procedures are not effective, potentially because of future conditions or risks outside of our control, we may be exposed to greater risk than we had intended. Ineffective risk-management policies and procedures or violation of risk-management policies and procedures could have an adverse affect on our earnings, financial position or cash flows.

Our use of financial instruments to hedge interest-rate risk may result in reduced income.

We and ONEOK Partners utilize financial instruments to mitigate our exposure to interest-rate fluctuations. Hedging instruments that are used to reduce our exposure to interest-rate fluctuations could expose us to risk of financial loss, including where we may contract for variable-rate swap instruments to hedge fixed-rate instruments and the variable rate exceeds the fixed rate. In addition,undertake these hedging arrangements may limit the benefit we would otherwise receive if we had contracted for fixed-rate swap agreements to hedge variable-rate instruments and the variable rate falls below the fixed rate.

An impairment of goodwill, long-lived assets, including intangible assets, and equity-method investments could reduce our earnings.

Goodwill is recorded when the purchase price of a business exceeds the fair market value of the tangible and separately measurable intangible net assets. GAAP requires us to test goodwill and intangible assets with indefinite useful lives for impairment on an annual basis or when events or circumstances occur indicating that goodwill might be impaired. Long-lived assets, including intangible assets with finite useful lives, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. For the investments ONEOK Partners accounts for under the equity method, the impairment test considers whether the fair value of the equity investment as a whole, not the underlying net assets, has declined and whether that decline is other than temporary. For example, if the current energy commodity price environment persists for a prolonged period or further declines, it could result in lower volumes delivered to ONEOK Partners’ systems and impairments of ONEOK Partners’ assets or equity-method investments. If we determine that an impairment is indicated, we would be required to take an immediate noncash charge to earnings with a correlative effect on our equity and balance sheet leverage as measured by consolidated debt to total capitalization.

A breach of information security, including a cybersecurity attack, or failure of one or more key information technology or operational systems, or those of third parties, may affect adversely our operations, financial results or reputation.

Our businesses are dependent upon our operational systems to process a large amount of data and complex transactions. The various uses of these IT systems, networks and services include, but are not limited to:
controlling ONEOK Partners’ plants and pipelines with industrial control systems including Supervisory Control and Data Acquisition (SCADA);
collecting and storing customer, employee, investor and other stakeholder information and data;
processing transactions;
summarizing and reporting results of operations;
hosting, processing and sharing confidential and proprietary research, business plans and financial information;
complying with regulatory, legal or tax requirements;
providing data security; and
handling other processing necessary to manage our business.

If any of our systems are damaged, fail to function properly or otherwise become unavailable, we may incur substantial costs to repair or replace them and may experience loss or corruption of critical data and interruptions or delays in our ability to perform critical functions, which could adversely affect our business and results of operations. Our financial results could also be affected adversely if an employee causes our operational systems to fail, either as a result of inadvertent error or by deliberately tampering with or manipulating our operational systems. In addition, dependence upon automated systems may further increase the risk that operational system flaws, employee tampering or manipulation of those systems will result in losses that are difficult to detect.

Due to increased technology advances, we have become more reliant on technology to help increase efficiency in our businesses. We use computer programs to help run our financial and operations organizations, and this may subject our business to increased risks. In recent years, there has been a rise in the number of cyberattacks on companies’ network and information systems by both state-sponsored and criminal organizations, and as a result, the risks associated with such an event continue to increase. A significant failure, compromise, breach or interruption in our systems could result in a disruption of our operations, customer dissatisfaction, damage to our reputation and a loss of customers or revenues. If any such failure, interruption or similar event results in the improper disclosure of information maintained in our information systems and

networks or those of our vendors, including personnel, customer and vendor information, we could also be subject to liability under relevant contractual obligations and laws and regulations protecting personal data and privacy. Efforts by us and our vendors to develop, implement and maintain security measures may not be successful in preventing these events from occurring, and any network and information systems-related events could require us to expend significant resources to remedy such event. Although we believe that we have robust information security procedures and other safeguards in place, as cyberthreats continue to evolve, we may be required to expend additional resources to continue to enhance our information security measures and/or to investigate and remediate information security vulnerabilities.

Cyberattacks against us or others in our industry could result in additional regulations. Current efforts by the federal government, such as the Improving Critical Infrastructure Cybersecurity executive order, and any potential future regulations could lead to increased regulatory compliance costs, insurance coverage cost or capital expenditures. We cannot predict the potential impact to our business or the energy industry resulting from additional regulations.

If we fail to maintain an effective system of internal controls,projects, we may not be able to report accurately complete them on schedule or at the budgeted cost;
our financial resultsrevenues may not increase immediately upon the expenditure of funds on a particular project. For instance, if we build a new pipeline, the construction will occur over an extended period of time, and we will not receive any material increases in revenues until after completion of the project;
we may construct facilities to capture anticipated future growth in production in a region in which anticipated production growth does not materialize;
opposition from environmental groups, landowners, tribal groups, local groups and other advocates could result in organized protests, attempts to block or sabotage our construction activities or operations, intervention in regulatory or administrative proceedings involving our assets, or lawsuits or other actions designed to prevent, fraud. disrupt or delay the construction or operation of our assets; and
we may be required to rely on third parties downstream of our facilities to have available capacity for our delivered natural gas or NGLs, which may not yet be operational.
As a result, current and potential holders of our equity and debt securities could lose confidence in our financial reporting, which would harm our business and cost of capital.

Effective internal controls are necessary for us to provide reliable financial reports, prevent fraud and operate successfully as a public company. We cannot be certain that our efforts to maintain our internal controls will be successful, that we willnew facilities may not be able to maintain adequate controls overattract enough natural gas or NGLs to achieve our financial processes and reporting in the future or that we will be able to continue to comply with our obligations under Section 404 of the Sarbanes-Oxley Act of 2002. Any failure to maintain effective internal controls, or difficulties encountered in implementing or improving our internal controls, could harm our operating results or cause us to fail to meet our reporting obligations. Ineffective internal controls could also cause investors to lose confidence in our reported financial information, which would likely have a negative effect on the trading price of our equity interests.

Changes in interest rates could affect adversely our business.

We use both fixed- and variable-rate debt, and we are exposed to market risk due to the floating interest rates on our short-term borrowings. From time to time, we use interest-rate derivatives to hedge interest obligations on specific debt issuances, including anticipated debt issuances. These hedges may be ineffective, and our results of operations, cash flows and financial position could be affected adversely by significant fluctuations or increases or decreases in interest rates from current levels.

A shortage of skilled labor may make it difficult for us to maintain labor productivity and competitive costs, which could affect operations and cash flows available for distribution.

Our operations require skilled and experienced workers with proficiency in multiple tasks. In recent years, a shortage of workers trained in various skills associated with the midstream energy business has caused us to conduct certain operations without full staff, thus hiring outside resources, which may decrease productivity and increase costs. This shortage of trained workers is the result of experienced workers reaching retirement age and increased competition for workers in certain areas, combined with the difficulty of attracting new workers to the midstream energy industry. This shortage of skilled labor could continue over an extended period. If the shortage of experienced labor continues or worsens, it could have an adverse impact on labor productivity and costs and our ability to expand production in the event there is an increase in the demand for our products and services,expected investment return, which could affect adversely our business, results of operations, financial position and cash flows availableflows.

Estimates of hydrocarbon reserves may be inaccurate which could result in lower than anticipated volumes.

We may not be able to accurately estimate hydrocarbon reserves and production volumes expected to be delivered to us for distributiona variety of reasons, including the unavailability of sufficiently detailed information and unanticipated changes in producers’ expected drilling schedules. Accordingly, we may not have accurate estimates of total reserves serviced by our assets, the anticipated life of such reserves or the expected volumes to ONEOK Partners’ unitholders and, in turn, to cash flows available for dividends to ONEOK shareholders.

ADDITIONAL RISKS RELATED TO ONEOK PARTNERS’ BUSINESS

Risks related to ONEOK Partners’ business discussed below will also affect us asbe produced from those reserves. In such event, if we are unable to secure additional sources, then the sole general partnervolumes that we gather or process in the future could be less than anticipated. A decline in such volumes could affect adversely our business, results of operations, financial position and as of December 31, 2016, owned 41.2 percent of ONEOK Partners.cash flows.

Increased competition could have a significant adverse financial impact on ONEOK Partners’ business.

The natural gas and natural gas liquids industries are expected to remain highly competitive. The demand for natural gas and NGLs is primarily a function of commodity prices, including prices for alternative energy sources, customer usage rates, weather, economic conditions and service costs. ONEOK Partners’ ability to compete also depends on a number of other factors, including competition from other companies for its existing customers; the efficiency, quality and reliability of the services it provides; and competition for throughput at its gathering systems, pipelines, processing plants, fractionators and storage facilities.



The volatility of natural gas, crude oil and NGL prices could affect adversely ONEOK Partners’our earnings and cash flows.


A significant portion of ONEOK Partners’our revenues are derived from the sale of commodities that are received as payment forin conjunction with natural gas gathering and processing services, for the transportation and storage of natural gas, and from the purchase and sale of NGLs and NGL products. Commodity prices have been volatile and are likely to continue to be so in the future. The prices ONEOK Partners receiveswe receive for itsour commodities are subject to wide fluctuations in response to a variety of factors beyond ONEOK Partners’our control, including, but not limited to, the following:
overall domestic and global economic conditions;
relatively minor changes in the supply of, and demand for, domestic and foreign energy;
market uncertainty;
the availability and cost of third-party transportation, natural gas processing and fractionation capacity;
the level of consumer product demand and storage inventory levels;
ethane rejection;
geopolitical conditions impacting supply and demand for natural gas, NGLs and crude oil;
weather conditions;
domestic and foreign governmental regulations and taxes;
the price and availability of alternative fuels;
speculation in the commodity futures markets;
the effects of imports and exports on the price of natural gas, crude oil, NGL and liquefied natural gas;
the effect of worldwide energy-conservation measures;
the impact of new supplies, new pipelines, processing and fractionation facilities on location price differentials; and
technology and improved efficiency impacting supply and demand for natural gas, NGLs and crude oil.

These external factors and the volatile nature of the energy markets make it difficult to reliably estimate future prices of commodities and the impact commodity price fluctuations have on ONEOK Partners’our customers and their need for its services.our services, which could affect adversely our business, results of operations, financial position and cash flows. As commodity prices decline, ONEOK Partners iswe could be paid less for itsour commodities, thereby reducing itsour cash flow.flows. In addition, crude oil, natural gas and NGL production could also decline due to lower prices.


If the level of drilling in the regions in which ONEOK Partners operates declines substantially near its assets, ONEOK Partners’ volumes and revenue could decline.

ONEOK Partners’ gathering and transportation pipeline systems are connected to, and dependent on the level of production from, natural gas and crude oil wells, from which production will naturally decline over time. As a result, its cash flows associated with these wells will also decline over time. In order to maintain or increase throughput levels on ONEOK Partners’ gathering and transportation pipeline systems and the asset utilization rates at its processing and fractionation plants, it must continually obtain new supplies. ONEOK Partners’ ability to maintain or expand its businesses depends largely on the level of drilling and production by third parties in the regions in which it operates. ONEOK Partners’ natural gas and NGL supply volumes may be impacted if producers curtail or redirect drilling and production activities. Drilling and production are impacted by factors beyond ONEOK Partners’ control, including:
demand and prices for natural gas, NGLs and crude oil;
producers’ access to capital;
producers’ finding and development costs of reserves;
producers’ desire and ability to obtain necessary permits in a timely and economic manner;
natural gas field characteristics and production performance;
surface access and infrastructure issues; and
capacity constraints on natural gas, crude oil and natural gas liquids infrastructure from the producing areas and ONEOK Partners’ facilities.
Commodity prices have declined substantially and experienced significant volatility. Drilling and production activity levels may vary across ONEOK Partners’ geographic areas; however, a prolonged period of low commodity prices may reduce drilling and production activities across all areas. If ONEOK Partners’ is not able to obtain new supplies to replace the natural decline in volumes from existing wells or because of competition, throughput on its gathering and transportation pipeline systems and the utilization rates of its processing and fractionation facilities would decline, which could have a material adverse effect on its business, results of operations, financial position and cash flows, and its ability to make cash distributions.


ONEOK Partners is exposed to the credit risk of its customers or counterparties, and its credit risk management may not be adequate to protect against such risk.

ONEOK Partners is subject to the risk of loss resulting from nonpayment and/or nonperformance by ONEOK Partners’ customers or counterparties. ONEOK Partners’ customers or counterparties may experience rapid deterioration of their financial condition as a result of changing market conditions, commodity prices or financial difficulties that could impact their creditworthiness or ability to pay ONEOK Partners for its services. ONEOK Partners assesses the creditworthiness of its customers or counterparties and obtains collateral or contractual terms as it deems appropriate. ONEOK Partners cannot, however, predict to what extent its business may be impacted by deteriorating market or financial conditions, including possible declines in its customers’ and counterparties’ creditworthiness. The recent decline in commodity prices has negatively impacted the financial condition of certain customers and counterparties and further declines, a prolonged low commodity price environment or continued volatility could impact their ability to meet their financial obligations to ONEOK Partners. ONEOK Partners’ customers and counterparties may not perform or adhere to its existing or future contractual arrangements. To the extent ONEOK Partners’ customers and counterparties are in financial distress or commence bankruptcy proceedings, contracts with them may be subject to renegotiation or rejection under applicable provisions of the United States Bankruptcy Code. If ONEOK Partners fails to assess adequately the creditworthiness of existing or future customers and counterparties, any material nonpayment or nonperformance by its customers and counterparties due to inability or unwillingness to perform or adhere to contractual arrangements could have a material adverse impact on ONEOK Partners’ business, results of operations, financial condition and ability to make cash distributions to its unitholders.

ONEOK Partners’ primary market areas are located in the Mid-Continent, Rocky Mountain, Permian Basin and Gulf Coast regions of the U.S. ONEOK Partners’ revenues are derived primarily from major integrated and independent exploration and production, pipeline, marketing and petrochemical companies. Therefore ONEOK Partners’ customers and counterparties may be similarly affected by changes in economic, regulatory or other factors that may affect its overall credit risk.

Some of ONEOK Partners’ nonregulated businesses have a higher level of risk than its regulated businesses.

Some of ONEOK Partners’ nonregulated operations, which include the Natural Gas Gathering and Processing segment and much of the Natural Gas Liquids segment, have a higher level of risk than its regulated operations, which include a portion of the Natural Gas Pipelines segment and a portion of the Natural Gas Liquids segment. ONEOK Partners expects to continue investing in natural gas and natural gas liquids projects and other related projects, some or all of which may involve nonregulated businesses or assets. These projects could involve risks associated with operational factors, such as competition and dependence on certain suppliers and customers; and financial, economic and political factors, such as rapid and significant changes in commodity prices, the cost and availability of capital and counterparty risk, including the inability of a counterparty, customer or supplier to fulfill a contractual obligation.

Measurement adjustments on ONEOK Partners’ pipeline system may be affected materially by changes in estimation, type of commodity and other factors.

Natural gas and natural gas liquids measurement adjustments occur as part of the normal operating conditions associated with ONEOK Partners’ assets. The quantification and resolution of measurement adjustments are complicated by several factors including: (1) the significant number (i.e., thousands) of meters that ONEOK Partners uses throughout its natural gas and natural gas liquids systems, primarily around its gathering and processing assets; (2) varying qualities of natural gas in the streams gathered and processed and the mixed nature of NGLs gathered and fractionated through ONEOK Partners’ systems; and (3) variances in measurement that are inherent in metering technologies. Each of these factors may contribute to measurement adjustments that can occur on ONEOK Partners’ systems, which could affect negatively its business, financial position, results of operations and cash flows.

Many of ONEOK Partners’ pipeline and storage assets have been in service for several decades.

Many of ONEOK Partners’ pipeline and storage assets are designed as long-lived assets. Over time the age of these assets could result in increased maintenance or remediation expenditures and an increased risk of product releases and associated costs and liabilities. Any significant increase in these expenditures, costs or liabilities could materially adversely affect ONEOK Partners’ results of operations, financial position or cash flows, as well as its ability to pay cash distributions.


ONEOK Partners doesWe do not hedge fully against commodity price risk or interest rate risk, including commodity price changes, seasonal price differentials, product price differentials or location price differentials. This could result in decreased revenues, increased costs and lower margins, affecting adversely affecting itsour results of operations.


Certain of ONEOK Partners’our businesses are exposed to market risk and the impact of market fluctuations ofin natural gas, NGLs and crude oil prices. Market risk refers to the risk of loss of future cash flows and future earnings arising from adverse changes in commodity prices. ONEOK Partners’Our primary commodity price exposures arise from:
the value of the NGLs and natural gascommodities sold under POP with fee contracts of which it retainswe retain a portion of the sales proceeds;
the price differentials between the individual NGL products with respect to ONEOK Partners’our NGL transportation and fractionation agreements;
the location price differentials in the price of natural gas and NGLs with respect to ONEOK Partners’ natural gas and NGL transportation businesses;NGLs;
the seasonal price differentials ofin natural gas and NGLs related to our storage operations;
the price risk related to electric costs to operate our facilities, primarily in Texas; and
the fuel costs and the value of the retained fuel in-kind in ONEOK Partners’our natural gas pipelines and storage operations.


To manage the risk from market price fluctuations ofin natural gas, NGLs and crude oil prices, ONEOK Partnerswe may use derivative instruments such as swaps, futures, forwards and options. However, it doeswe do not hedge fully against commodity price changes, and we therefore it retainsretain some exposure to market risk. Accordingly, any adverse changes to commodity prices could result in decreased revenue and increased costs.

ONEOK Partners’ use of financial instruments and physical forward transactions to hedge market-risk exposure to commodity price and interest-rate fluctuations may result in reduced income.

ONEOK Partners utilizes financial instruments and physical forward transactions to mitigate its exposure to interest rate and commodity price fluctuations. HedgingFurther, hedging instruments that are used to reduce ONEOK Partners’our exposure to interest-rate fluctuations could expose itus to risk of financial loss where itwe may contract for variable-ratefixed-rate swap instruments to hedge fixed-rate instruments and the variable rate exceeds the fixed rate. In addition, these hedging arrangements may limit the benefit ONEOK Partners would otherwise receive if it had contracted for fixed-rate swap agreements to hedge variable-rate instruments and the fixed rate exceeds the variable rate falls below the fixed rate. HedgingFinally, hedging arrangements thatfor forecasted sales and purchases are used to reduce ONEOK Partners’our exposure to commodity price fluctuations and may limit the benefit itwe would otherwise receive if market prices for natural gas, crude oil and NGLs exceeddiffer from the stated price in the hedge instrument for these commodities.


ONEOK Partners may not be able to develop and execute growth projects and acquire new assets, which could result in reduced cash distributions to its unitholders and to ONEOK.

ONEOK Partners’ primary business objectives are to generate cash flow sufficient to pay quarterly cash distributions to its unitholders and to increase its quarterly cash distributions over time. ONEOK Partners’ ability to maintain and grow its distributions to unitholders depends on the growthA breach of its existing businesses and strategic acquisitions. ONEOK Partners’ ability to make strategic acquisitions and investments will depend on:
the extent to which acquisitions and investment opportunities become available;
ONEOK Partners’ success in bidding for the opportunities that do become available;
regulatory approval, if required,information security, including a cybersecurity attack, or failure of the acquisitionsone or investments on favorable terms; and
ONEOK Partners’ access to capital, including its ability to use its equity in acquisitionsmore key information technology or investments, and the terms upon which it obtains capital.

ONEOK Partners’ ability to develop and execute growth projects will depend on its ability to implement business development opportunities and finance such activities on economically acceptable terms.

If ONEOK Partners is unable to make strategic acquisitions and investments, integrate successfully businesses that it acquires with its existing business,operational systems, or develop and execute its growth projects, its future growth will be limited, which could adversely impact ONEOK Partners’ resultsthose of operations and cash flows and, accordingly, result in reduced cash distributions over time.


Growing ONEOK Partners’ business by constructing new pipelines and plants or making modifications to its existing facilities subjects ONEOK Partners to construction risk and supply risks should adequate natural gas or NGL supply be unavailable upon completion of the facilities.

One of the ways ONEOK Partners may grow its businesses is through the construction of new pipelines and new gathering, processing, storage and fractionation facilities and through modifications to ONEOK Partners’ existing pipelines and existing gathering, processing, storage and fractionation facilities. The construction and modification of pipelines and gathering, processing, storage and fractionation facilities may face the following risks:
projects may require significant capital expenditures, which may exceed ONEOK Partners’ estimates, and involves numerous regulatory, environmental, political, legal and weather-related uncertainties;
projects may increase demand for labor, materials and rights of way, which may, in turn, affect ONEOK Partners’ costs and schedule;
ONEOK Partners may be unable to obtain new rights of way to connect new natural gas or NGL supplies to its existing gathering or transportation pipelines;
if ONEOK Partners undertakes these projects, it may not be able to complete them on schedule or at the budgeted cost;
ONEOK Partners’ revenues may not increase immediately upon the expenditure of funds on a particular project.  For instance, if ONEOK Partners builds a new pipeline, the construction will occur over an extended period of time, and it will not receive any material increases in revenues until after completion of the project;
ONEOK Partners’ may have only limited natural gas or NGL supply committed to these facilities prior to their construction;
ONEOK Partners may construct facilities to capture anticipated future growth in production in a region in which anticipated production growth does not materialize;
ONEOK Partners may rely on estimates of proved reserves in its decision to construct new pipelines and facilities, which may prove to be inaccurate because there are numerous uncertainties inherent in estimating quantities of proved reserves; and
ONEOK Partners may be required to rely on third parties, downstream of its facilities to have available capacity for its delivered natural gas or NGLs, which may not yet be operational.
As a result, new facilities may not be able to attract enough natural gas or NGLs to achieve ONEOK Partners’ expected investment return, which could affect materially and adversely ONEOK Partners’ results ofour operations, financial condition and cash flows.results or reputation.


If production from the Western Canada Sedimentary Basin remains flat or declines, and demand for natural gas from the Western Canada Sedimentary Basin is greater in market areas other than the Midwestern United States, demand for ONEOK Partners’ interstate gas transportation services could decrease significantly.

ONEOK Partners depends onOur businesses are dependent upon our operational systems to process a portion of natural gas supply from the Western Canada Sedimentary Basin for some of ONEOK Partners’ interstate pipelines, primarily Viking Gas Transmission and ONEOK Partners’ investment in Northern Border Pipeline, that transport Canadian natural gas from the Western Canada Sedimentary Basin to the Midwestern United States market area. If demand for natural gas increases in Canada or other markets not served by ONEOK Partners’ interstate pipelines and/or production remains flat or declines, demand for transportation service on ONEOK Partners’ interstate natural gas pipelines could decrease significantly, which could impact adversely its and our results of operations and cash flows.

ONEOK Partners may not be able to replace, extend or add additional customer contracts or contracted volumes on favorable terms, or at all, which could affect ONEOK Partners’ financial condition, thelarge amount of cash available to pay distributionsdata and its ability to grow.

Although manycomplex transactions. The various uses of ONEOK Partners’ customersthese information technology systems, networks and suppliers are subject to long-term contracts, if it is unable to replace or extend such contracts, add additional customers or otherwise increase the contracted volumes of natural gas and NGLs provided to it by current producers, in each case on favorable terms, if at all, ONEOK Partners’ financial condition, growth plans and the amount of cash available to pay distributions could be adversely affected. ONEOK Partners’ ability to replace, extend or add additional customer or supplier contracts, or increase contracted volumes of natural gas and NGLs from current producers, on favorable terms, or at all, is subject to a number of factors, some of which are beyond ONEOK Partners’ control, including:
the level of existing and new competition in ONEOK Partners’ businesses or from alternative fuel sources, such as electricity, coal, fuel oils or nuclear energy;
natural gas and NGL prices, demand, availability; and

margins in ONEOK Partners’ markets.

Mergers between ONEOK Partners’ customers and competitors could result in lower volumes being gathered, processed, fractionated, transported or stored on its assets, thereby reducing the amount of cash it generates.

Mergers between ONEOK Partners’ existing customers and its competitors could provide strong economic incentives for the combined entities to utilize their existing gathering, processing, fractionation and/or transportation systems instead of ONEOK Partners’ in those markets where the systems compete. As a result, ONEOK Partners could lose some or all of the volumes and associated revenues from these customers, and it could experience difficulty in replacing those lost volumes and revenues. Because most of ONEOK Partners’ operating costs are fixed, a reduction in volumes could result not only in less revenue but also in a decline in cash flow, which would reduce its ability to pay cash distributions to its unitholders.

ONEOK Partners is subject to strict regulations at many of its facilities regarding employee safety, and failure to comply with these regulations could affect adversely ONEOK Partners’ business, financial position, results of operations and cash flows.

The workplaces associated with ONEOK Partners’ facilities are subject to the requirements of OSHA and comparable state statutes that regulate the protection of the health and safety of workers. The failure to comply with OSHA requirements or general industry standards, including keeping adequate records or occupational exposure to regulated substances could expose it to civil or criminal liability, enforcement actions, and regulatory fines and penalties and could have a material adverse effect on ONEOK Partners’ business, financial position, results of operations and cash flows.

ONEOK Partners’ operations are subject to operational hazards and unforeseen interruptions that could affect materially and adversely ONEOK Partners’ business and for which neither we nor ONEOK Partners may be insured adequately.

ONEOK Partners’ operations are subject to all of the risks and hazards typically associated with the operation of natural gas and natural gas liquids gathering, transportation and distribution pipelines, storage facilities and processing and fractionation plants. Operating risksservices include, but are not limited to:
controlling our plants and pipelines with industrial control systems including Supervisory Control and Data Acquisition (SCADA);
collecting and storing customer, employee, investor and other stakeholder information and data;
processing transactions;
summarizing and reporting results of operations;
hosting, processing and sharing confidential and proprietary research, business plans and financial information;
complying with regulatory, legal, financial or tax requirements;
providing data security; and
other processes necessary to leaks, pipeline ruptures, the breakdownmanage our business.

If any of our systems are damaged, fail to function properly or failureotherwise become unavailable, we may incur substantial costs to repair or replace them and may experience loss or corruption of equipmentcritical data and interruptions or processes, and the performance of pipeline facilities below expected levels of capacity and efficiency. Other operational hazards and unforeseen interruptions include adverse weather conditions, accidents, explosions, fires, the collision of equipment with ONEOK Partners’ pipeline facilities (for example, this may occur if a third party weredelays in our ability to perform excavation or construction work near ONEOK Partners’ facilities) and catastrophic events such as tornados, hurricanes, earthquakes, floods or other similar events beyond ONEOK Partners’ control. It is also possible that ONEOK Partners’ facilitiescritical functions, which could be direct targets or indirect casualties of an act of terrorism. A casualty occurrence might result in injury or loss of life, extensive property damage or environmental damage. Liabilities incurred and interruptions to the operations of ONEOK Partners’ pipelines or other facilities caused by such an event could reduce revenues generated by ONEOK Partners and increase expenses, thereby impairingaffect adversely our or ONEOK Partners’ ability to meet our respective obligations.  Insurance proceeds may not be adequate to cover all liabilities or expenses incurred or revenues lost, and neither we nor ONEOK Partners are fully insured against all risks inherent in our respective businesses.

As a result of market conditions, premiums and deductibles for certain insurance policies can increase substantially, and, in some instances, certain insurance may become unavailable or available only for reduced amounts of coverage. Consequently, neither we nor ONEOK Partners may be able to renew existing insurance policies or purchase other desirable insurance on commercially reasonable terms, if at all. If either we or ONEOK Partners were to incur a significant liability for which either we or ONEOK Partners was not insured fully, it could have a material adverse effect on our or ONEOK Partners’ financial positionbusiness and results of operations. Further,Our financial results could also be affected adversely if an individual causes our operational systems to fail, either as a result of inadvertent error or by deliberately tampering with or manipulating our operational systems. In addition, dependence upon automated systems may further increase the proceedsrisk that operational system flaws, employee tampering or manipulation of those systems will result in losses that are difficult to detect.

Due to increased technology advances, we have become more reliant on technology to help increase efficiency in our businesses. We use software to help manage and operate our businesses, and this may subject us to increased risks. In recent years, there has been a rise in the number and sophistication of cyberattacks on companies’ network and information systems by both state-sponsored and criminal organizations, and as a result, the risks associated with such an event continue to increase. A significant failure, compromise, breach or interruption in our systems could result in a disruption of our operations, physical

damages, customer dissatisfaction, damage to our reputation and a loss of customers or revenues. If any such insurancefailure, interruption or similar event results in the improper disclosure of information maintained in our information systems and networks or those of our vendors, including personnel, customer and vendor information, we could also be subject to liability under relevant contractual obligations and laws and regulations protecting personal data and privacy. Efforts by us and our vendors to develop, implement and maintain security measures may not be paidsuccessful in preventing these events from occurring, and any network and information systems-related events could require us to expend significant resources to remedy such event. Cybersecurity, physical security and the continued development and enhancement of our controls, processes and practices designed to protect our enterprise, information systems and data from attack, damage or unauthorized access and to identify and appropriately report cyberattacks, remain a timely mannerpriority for us. Although we believe that we have robust information security procedures and other safeguards in place, as cyberthreats continue to evolve, we may be insufficient if such an event wererequired to occur.expend additional resources to continue to enhance our information security measures and/or to investigate and remediate information security vulnerabilities.


ONEOK Partners does not own all of the land on which its pipelines and facilities are located, and it leases certain facilities and equipment, which could disrupt its operations.

ONEOK Partners does not own all of the land on which certain of its pipelines and facilities are located and are, therefore, subject to the risk of increased costs to maintain necessary land use. ONEOK Partners obtains the rights to construct and operate certain of its pipelines and related facilities on land owned by third parties and governmental agencies for a specific period of time. Loss of these rights, through its inability to renew right-of-way contracts on acceptable termsCyberattacks against us or increased costs to renew such rights, could have a material adverse effect on ONEOK Partners’ financial condition, results of operations and cash flows.


Pipeline safety laws and regulations may impose significant costs and liabilities.

Pipeline safety legislation that was signed into lawothers in 2012, the 2011 Pipeline Safety Act, directed the Secretary of Transportation to promulgate new safety regulations for natural gas and hazardous liquids pipelines, including expanded integrity management requirements, automatic or remote-controlled valve use, excess flow valve use, leak detection system installation, testing to confirm the material strength of certain pipelines and operator verification of records confirming the maximum allowable pressure of certain gas transmission pipelines. The 2011 Pipeline Safety Act also increased the maximum penalty for violation of pipeline safety regulations from $100,000 to $200,000 per violation per day and also from $1 million to $2 million for a related series of violations.

The 2011 Pipeline Safety Act, the PIPES Act or rules implementing such acts could cause ONEOK Partners to incur capital and operating expenditures for pipeline replacements or repairs, additional monitoring equipment or more frequent inspections or testing of its pipeline facilities, preventive or mitigating measures and other tasks thatour industry could result in higher operatingadditional regulations. Current efforts by the federal government, such as the Improving Critical Infrastructure Cybersecurity executive order, and any potential future regulations could lead to increased regulatory compliance costs, insurance coverage cost or capital expenditures as necessary to comply with such standards, which costs could be significant.

See further discussion in the “Regulatory, Environmental and Safety Matters” section.

ONEOK Partners is subject to comprehensive energy regulation by governmental agencies, and the recovery of its costs are dependent on regulatory action.

Federal, state and local agencies have jurisdiction over many of ONEOK Partners’ activities, including regulation by the FERC of its interstate pipeline assets. The profitability of ONEOK Partners’ regulated operations is dependent on its ability to pass through costs related to providing energy and other commodities to its customers by filing periodic rate cases. The regulatory environment applicable to ONEOK Partners’ regulated businesses could impair its ability to recover costs historically absorbed by its customers.

ONEOK Partners is unable toexpenditures. We cannot predict the potential impact that the future regulatory activities of these agencies will have on its operating results. Changes in regulationsto our business or the imposition ofenergy industry resulting from additional regulations could have an adverse impact on ONEOK Partners’ business, financial condition and results of operations.regulations.


ONEOK Partners’ regulated pipelines’ transportation rates are subject to review and possible adjustment by federal and state regulators.

Under the Natural Gas Act, which is applicable to interstate natural gas pipelines, and the Interstate Commerce Act, which is applicable to crude oil and natural gas liquids pipelines, ONEOK Partners’ interstate transportation rates, which are regulated by the FERC, must be just and reasonable and not unduly discriminatory.

Under current policy, the FERC permits interstate pipelines that are subject to cost of service regulation to include an income tax allowance when calculating their regulated rates. The FERC’s income tax allowance policy has been the subject of challenge, and ONEOK Partners cannot predict whether the FERC or a reviewing court will alter the existing policy. For example, on July 1, 2016, the U.S. Court of Appeals for the District of Columbia Circuit issued a decision that calls into question a decade of FERC policy and precedent permitting regulated companies organized as pass-through entities for income tax purposes to include an allowance for income taxes in their rates. The court has remanded the case to the FERC to allow it to have an opportunity to provide a reasoned basis for its decision on income tax allowances for partnership pipelines. The FERC has issued a Notice of Inquiry seeking comments on proposed methods to adjust FERC’s income tax policy. Comments are due in March 2017. If the FERC’s policy were to change and if the FERC were to disallow a substantial portion of ONEOK Partners’ pipelines’ income tax allowance, its regulated rates, and therefore ONEOK Partners’ revenues and ability to make quarterly cash distributions to its unitholders, could be adversely affected.

If ONEOK Partners were permitted to raise its tariff rates for a particular pipeline, there might be significant delay between the time the tariff rate increase is approved and the time that the rate increase actually goes into effect, which if delayed could further reduce ONEOK Partners’ cash flow. Furthermore, competition from other pipeline systems may prevent ONEOK Partners from raising its tariff rates even if regulatory agencies permit it to do so. The regulatory agencies that regulate ONEOK Partners’ systems periodically implement new rules, regulations and terms and conditions of services subject to their jurisdiction. New initiatives or orders may adversely affect the rates charged for ONEOK Partners’ services.

Finally, shippers may protest ONEOK Partners’ pipeline tariff filings, and the FERC and or state regulatory agency may investigate tariff rates. Further, the FERC may order refunds of amounts collected under newly filed rates that are determined by the FERC to be in excess of a just and reasonable level. In addition, shippers may challenge by complaint the lawfulness of

tariff rates that have become final and effective. The FERC and/or state regulatory agencies also may investigate tariff rates absent shipper complaint. Any finding that approved rates exceed a just and reasonable level on the natural gas pipelines would take effect prospectively. In a complaint proceeding challenging natural gas liquids pipeline rates, if the FERC determines existing rates exceed a just and reasonable level, it could require the payment of reparations to complaining shippers for up to two years prior to the complaint. Any such action by the FERC or a comparable action by a state regulatory agency could affect adversely ONEOK Partners’ pipeline businesses’ ability to charge rates that would cover future increases in costs, or even to continue to collect rates that cover current costs, and provide for a reasonable return. ONEOK Partners’ can provide no assurance that its pipeline systems will be able to recover all of its costs through existing or future rates.

ONEOK Partners’ regulated pipeline companies have recorded certain assets that may not be recoverable from its customers.

Accounting policies for FERC-regulated companies permit certain assets that result from the regulated rate-making process to be recorded on ONEOK Partners’ balance sheet that could not be recorded under GAAP for nonregulated entities. ONEOK Partners considers factors such as regulatory changes and the impact of competition to determine the probability of future recovery of these assets. If ONEOK Partners determines future recovery is no longer probable, ONEOK Partners would be required to write off the regulatory assets at that time.

Compliance with environmental regulations that ONEOK Partners is subject to may be difficult and costly.

ONEOK Partners is subject to multiple environmental laws and regulations affecting many aspects of present and future operations, including air emissions, water quality, wastewater discharges, solid and hazardous wastes, and hazardous material and substance management. These laws and regulations require ONEOK Partners to obtain and comply with a wide variety of environmental registrations, licenses, permits, inspections and other approvals. Failure to comply with these laws, regulations, permits and licenses may expose ONEOK Partners to fines, penalties and/or interruptions in its operations that could be material to its results of operations. If a leak or spill of hazardous substance occurs from ONEOK Partners’ pipelines, gathering lines or facilities in the process of transporting natural gas or NGLs or at any facility that ONEOK Partners owns, operates or otherwise uses, ONEOK Partners could be held jointly and severally liable for all resulting liabilities, including investigation and clean-up costs, which could affect materially its results of operations and cash flows. In addition, emission controls required under the federal Clean Air Act and other similar federal and state laws could require unexpected capital expenditures at ONEOK Partners’ facilities. ONEOK Partners cannot assure that existing environmental regulations will not be revised or that new regulations will not be adopted or become applicable to it. Revised or additional regulations that result in increased compliance costs or additional operating restrictions, particularly if those costs are not fully recoverable from customers, could have a material adverse effect on ONEOK Partners’ business, financial condition and results of operations.

ONEOK Partners’Our operations are subject to federal and state laws and regulations relating to the protection of the environment, which may expose itus to significant costs and liabilities.


The risk of incurring substantial environmental costs and liabilities is inherent in ONEOK Partners’our business. ONEOK Partners’Our operations are subject to extensive federal, state and local laws and regulations governing the discharge of materials into, or otherwise relating to the protection of, the environment. Examples of these laws include:
the Clean Air Act and analogous state laws that impose obligations related to air emissions;
the Clean Water Act and analogous state laws that regulate discharge of waste waterwastewater from ONEOK Partners’our facilities to state and federal waters;
the federal CERCLAComprehensive Environmental Response, Compensation and Liability Act (CERCLA) and analogous state laws that regulate the cleanup of hazardous substances that may have been released at properties currently or previously owned or operated by ONEOK Partnersus or locations to which ONEOK Partners haswe have sent waste for disposal; and
the federal Resource Conservation and Recovery Act and analogous state laws that impose requirements for the handling and discharge of solid and hazardous waste from ONEOK Partners’our facilities.


Various federal and state governmental authorities, including the EPA, have the power to enforce compliance with these laws and regulations and the permits issued under them. Violators are subject to administrative, civil and criminal penalties, including civil fines, injunctions or both. Joint and several, strict liability may be incurred without regard to fault under the CERCLA, Resource Conservation and Recovery Act and analogous state laws for the remediation of contaminated areas.


There is an inherent risk of incurring environmental costs and liabilities in ONEOK Partners’our business due to itsour handling of the products it gathers, transports, processeswe gather, transport, process and stores,store, air emissions related to itsour operations, past industry operations and waste disposal practices, some of which may be material. Private parties, including the owners of properties through which ONEOK

Partners’our pipeline systems pass, may have the right to pursue legal actions to enforce compliance as well as to seek damages for noncompliance with environmental laws and regulations or for personal injury or property damage arising from ONEOK Partners’our operations. Some sites ONEOK Partners operateswe operate are located near current or former third-party hydrocarbon storage and processing operations, and there is a risk that contamination has migrated from those sites to ONEOK Partners’ sites.ours. In addition, increasingly strict laws, regulations and enforcement policies could increase significantly ONEOK Partners’our compliance costs and the cost of any remediation that may become necessary, some of which may be material. Additional information is included under Item 1, Business, under “Regulatory, Environmental and Safety Matters” and in Note PN of the Notes to Consolidated Financial Statements in this Annual Report.


ONEOK Partners’Our insurance may not cover all environmental risks and costs or may not provide sufficienthas limits on coverage in the event an environmental claim is made against ONEOK Partners. ONEOK Partners’us. Our business may be affected materially and adversely by increased costs due to stricter pollution-control requirements or liabilities resulting from noncompliance with required operating or other regulatory permits. New or revised environmental regulations might also materially andaffect adversely affect ONEOK Partners’our products and activities, and federal and state agencies could impose additional safety requirements, all of which could affect materially ONEOK Partners’adversely our profitability.


ONEOK PartnersWe may face significant costs to comply with the regulation of GHG emissions.


GHG emissions originate primarily from combustion engine exhaust, heater exhaust and fugitive methane gas emissions. International, federal, regional and/or state legislative and/or regulatory initiatives may attempt to control or limit GHG emissions, including initiatives directed at issues associated with climate change. Various federal and state legislative proposals have been introduced to regulate the emission of GHGs, particularly carbon dioxide and methane, and the United States Supreme Court has ruled that carbon dioxide is a pollutant subject to regulation by the EPA. In addition, there have been international efforts seeking legally binding reductions in emissions of GHGs.


ONEOK Partners believesWe believe it is likely that future governmental legislation and/or regulation on the federal, state and regional levels, may require itus either to limit GHG emissions from itsassociated with our operations, pay additional taxes or to purchase allowances for such emissions thatemissions. These legislative and/or regulatory initiatives could make some of our activities uneconomic to maintain or operate. Further, we may not be able to pass on the higher costs to our customers or recover all costs related to complying with GHG regulatory requirements. Our future results of operations, financial position or cash flows could be affected adversely if such costs are actually attributablenot recovered or otherwise passed on to its NGLour customers. However, itwe cannot predict precisely what form these future regulations will take, the stringency of the regulations or when they willmay become effective. Several legislative bills have been introduced in the United States Congress that would require carbon dioxide emission reductions. Previously considered proposals have included, among other things, limitations on the amount of GHGs that can be emitted (so called “caps”) together with systems of emissions allowances. These proposals could require ONEOK Partners to reduce emissions, even though the technology is not currently available for efficient reduction, or to purchase allowances for such emissions. Emissions also could be taxed independently of limits.


In addition to activities on the federal level, state and regional initiatives could also lead to the regulation of GHG emissions sooner and/or independent of federal regulation. These regulations could be more stringent than any federal legislation that is adopted.

Future legislation and/or regulation designed to reduce GHG emissions could make some of its activities uneconomic to maintain or operate. Further, ONEOK Partners may not be able to pass on the higher costs to its customers or recover all costs related to complying with GHG regulatory requirements. Its future results of operations, cash flows or financial condition could be adversely affected if such costs are not recovered through regulated rates or otherwise passed on to its customers.

ONEOK Partners continues to monitor legislative and regulatory developments in this area. Although the regulation of GHG emissions may have a material impact on its operations and rates, ONEOK Partners believes it is premature to attempt to quantify the potential costs of the impacts.

ONEOK PartnersWe may be subject to physical and financial risks associated with climate change.change and changes in investor sentiment towards climate change may affect the demand for our securities.


There is a growing belief that emissionsThe threat of GHGs may be linked to global climate change. Climate change createsmay create physical and financial risk. ONEOK Partners’risks to our business. Our customers’ energy needs vary with weather conditions, primarily temperature and humidity. For residential customers, heating and cooling represent their largest energy use. To the extent weather conditions may be affected by climate change, customers’ energy use could increase or decrease depending on the duration and magnitude of any changes. Increased energy use due to weather changes may require ONEOK Partnersus to invest in more pipelines and other infrastructure to serve increased demand. A decrease in energy use due to weather changes may affect itsour financial condition, through decreased revenues. Extreme weather conditions in general require more system backup, adding to costs, and can contribute to increased system stresses, including service interruptions. Weather conditions outside of ONEOK Partners’our operating territory could also have an impact on itsour revenues. Severe weather impacts itsour operating territories primarily through hurricanes, thunderstorms, tornados and snow or ice storms. To the extent the frequency of extreme weather events increases, this could increase itsour cost of providing service. ONEOK PartnersWe may not be able to pass on the higher costs to itsour customers or recover all the costs related to mitigating these physical risks. To

Due to climate change concerns, some investors may choose to either not invest, or reduce their investment, in companies that explore for, produce, process, transport or sell products derived from hydrocarbons. If this investor sentiment increases, we may see reduced demand for our securities, which could impact our liquidity or the value of our securities. In addition, to the extent financial markets view climate change and

emissions of GHGs as a financial risk, this could affect negatively itsour ability to access capital markets or cause ONEOK Partnersus to receive less favorable terms and conditions in future financings. Its business

Changes in regulatory policies, public sentiment or technology due to the threat of climate change that result in a reduction in the demand for hydrocarbon products, restrictions on their use, or increased use of renewable energy could be affected byreduce future demand for hydrocarbons and reduce volumes available to us for gathering, processing, fractionation, transportation, storage and marketing. Finally, increasing attention to climate change and the potential for lawsuits against GHG emitters, based on links drawn betweenimpacts of GHG emissions has resulted in an increased likelihood of governmental investigations, regulation and climate change.private litigation, which could increase our costs or otherwise affect adversely our business.


ONEOK Partners’Our business is subject to regulatory oversight and potential penalties.


The natural gasenergy industry historically has been subject to heavy state and federal regulation that extends to many aspects of ONEOK Partners’our businesses and operations, including:
regulatory approval and review of certain of our rates, operating terms and conditions of service;
the types of services ONEOK Partnerswe may offer it customers;our counterparties;
construction of new facilities;
the integrity, safety and security of facilities and operations;
acquisition, extension or abandonment of services or facilities;
reporting and information posting requirements;
maintenance of accounts and records; and
relationships with affiliate companies involved in all aspects of the natural gas and energy businesses.


Compliance with these requirements can be costly and burdensome. Future changes to laws, regulations and policies in these areas may impair ONEOK Partners’our ability to compete for business or to recover costs and may increase the cost and burden of our operations. ONEOK PartnersWe cannot guarantee that state or federal regulators will not challenge our safety practices or will authorize any projects or acquisitions that itwe may propose in the future. Moreover, ONEOK Partners cannotthere can be no guarantee that, if granted, any such authorizations will be made in a timely manner or will be free from potentially burdensome conditions.


Under the Natural Gas Act, which is applicable to our interstate natural gas pipelines, and the Interstate Commerce Act, which is applicable to our NGL pipelines, our interstate transportation rates are regulated by the FERC and many changes to our pipeline tariffs must be approved in a regulatory proceeding. Additionally, either shippers, the FERC and/or state regulatory agencies may investigate our tariff rates which could result in, among other things, being ordered to reduce rates or make refunds to shippers.

Failure to comply with all applicable state or federal statutes, rules and regulations and orders could bring substantial penalties and fines. For example,

Our regulated pipeline companies have recorded certain assets that may not be recoverable from our customers.

Accounting policies for FERC-regulated companies permit certain assets that result from the regulated rate-making process to be recorded on our balance sheet that could not be recorded under GAAP for nonregulated entities. We consider factors such as regulatory changes and the Energy Policy Actimpact of 2005,competition to determine the FERCprobability of future recovery of these assets. If we determine future recovery is no longer probable, we would be required to write off the regulatory assets at that time.

A shortage of skilled labor may make it difficult for us to maintain labor productivity and competitive costs.

Our operations require skilled and experienced workers with proficiency in multiple tasks. In recent years, a shortage of workers trained in various skills associated with the midstream energy business has, civil penalty authority underat times, caused us to conduct certain operations without full staff, thus hiring outside resources, which may decrease productivity and increase costs. This shortage of trained workers is the result of experienced workers reaching retirement age and increased competition for workers in certain areas, combined with the challenges of attracting new, qualified workers to the midstream energy industry. This shortage of skilled labor could continue over an extended period. If the shortage of experienced labor continues or worsens, it could affect adversely our labor productivity and costs and our ability to expand operations in the event there is an increase in the demand for our services and products, which could affect adversely our business, results of operations, financial position and cash flows.

Measurement adjustments on our pipeline system may be impacted materially by changes in estimation, type of commodity and other factors.

Natural Gas Actgas and NGL measurement adjustments occur as part of the normal operating conditions associated with our assets. The quantification and resolution of measurement adjustments are complicated by several factors including: (i) the significant quantities (i.e., thousands) of measurement equipment that we use across our natural gas and NGL systems, primarily around our gathering and processing assets; (ii) varying qualities of natural gas in the streams gathered and processed through our systems and the mixed nature of NGLs gathered and fractionated; and (iii) variances in measurement that are inherent in metering technologies. Each of these factors may contribute to impose penaltiesmeasurement adjustments that may occur on our systems, which could affect adversely our business, results of operations, financial position and cash flows.

Many of our assets have been in service for current violationsseveral decades.

Many of our pipeline and storage assets are designed as long-lived assets. Over time the age of these assets could result in increased maintenance or remediation expenditures and an increased risk of product releases and associated costs and liabilities. Any significant increase in these expenditures, costs or liabilities could affect adversely our business, results of operations, financial position and cash flows, as well as our ability to pay cash dividends.

We may be unable to cause our joint ventures to take or not to take certain actions unless some or all of our joint-venture participants agree.

We participate in several joint ventures. Due to the nature of some of these arrangements, each participant in these joint ventures has made substantial investments in the joint venture and, accordingly, has required that the relevant charter documents contain certain features designed to provide each participant with the opportunity to participate in the management of the joint venture and to protect its investment, as well as any other assets that may be substantially dependent on or

otherwise affected by the activities of that joint venture. These participation and protective features customarily include a corporate governance structure that requires at least a majority-in-interest vote to authorize many basic activities and requires a greater voting interest (sometimes up to $1 million per day for each violation.

Finally, ONEOK Partners cannot give100%) to authorize more significant activities. Examples of these more significant activities are large expenditures or contractual commitments, the construction or acquisition of assets, borrowing money or otherwise raising capital, transactions with affiliates of a joint-venture participant, litigation and transactions not in the ordinary course of business, among others. Thus, without the concurrence of joint-venture participants with enough voting interests, we may be unable to cause any assurance regarding future stateof our joint ventures to take or federal regulations under which it will operatenot to take certain actions, even though those actions may be in the best interest of us or the effectparticular joint venture.

Moreover, subject to contractual restrictions, any joint-venture owner generally may sell, transfer or otherwise modify its ownership interest in a joint venture, whether in a transaction involving third parties or the other joint-venture owners. Any such regulationstransaction could result in us being required to partner with different or additional parties who may have business interests different from ours.

We do not operate all of our joint-venture assets nor do we employ directly all of the persons responsible for providing administrative, operating and management services. This reliance on itsothers to operate joint-venture assets and to provide other services could affect adversely our business and results of operations.

We rely on others to provide administrative, operating and management services for certain of our joint-venture assets. We have a limited ability to control the operations and the associated costs of such operations. The success of these operations depends on a number of factors that are outside our control, including the competence and financial resources of the operator or an outsourced service provider. We may have to contract elsewhere for outsourced services, which may cost more than we are currently paying. In addition, we may not be able to obtain the same level or kind of service or retain or receive the services in a timely manner, which may impact our ability to perform under our contracts and affect adversely our business and results of operations.

We do not own all of the land on which our pipelines and facilities are located, and we lease certain facilities and equipment, which could disrupt our operations.

We do not own all of the land on which certain of our pipelines and facilities are located, and we are, therefore, subject to the risk of increased costs to maintain necessary land use. We obtain the rights to construct and operate certain of our pipelines and related facilities on land owned by third parties and governmental agencies for a specific period of time. Our loss of these rights, through our inability to renew right-of-way contracts on acceptable terms or increased costs to renew such rights, could affect adversely our business, results of operations, financial position and cash flows.

Acquisitions that appear to be accretive may nevertheless reduce our cash from operations on a per-share basis.

Any acquisition involves potential risks that may include, among other things:
inaccurate assumptions about volumes, revenues and costs, including potential synergies;
an inability to integrate successfully the businesses we acquire;
decrease in our liquidity as a result of our using a significant portion of our available cash or borrowing capacity to finance the acquisition;
a significant increase in our interest expense and/or financial leverage if we incur additional debt to finance the acquisition;
the assumption of unknown liabilities for which we are not indemnified, our indemnity is inadequate or our insurance policies may exclude from coverage;
an inability to hire, train or retain qualified personnel to manage and operate the acquired business financial conditionand assets;
limitations on rights to indemnity from the seller;
inaccurate assumptions about the overall costs of equity or debt;
the diversion of management’s and employees’ attention from other business concerns;
unforeseen difficulties operating in new product areas or new geographic areas;
increased regulatory burdens;
customer or key employee losses at an acquired business; and
increased regulatory requirements.

If we consummate any future acquisitions, our capitalization and results of operations may change significantly, and cash flows.investors will not have the opportunity to evaluate the economic, financial and other relevant information that we will consider in determining the application of our resources to future acquisitions.

DemandIf we fail to maintain an effective system of internal controls, we may not be able to report accurately our financial results or prevent fraud. As a result, current and potential holders of our equity and debt securities could lose confidence in our financial reporting.

Effective internal controls are necessary for natural gasus to provide reliable financial reports, prevent fraud and foroperate successfully as a public company. We cannot be certain of ONEOK Partners’ productsthat our efforts to maintain our internal controls will be successful, that we will be able to maintain adequate controls over our financial processes and services is highly weather sensitive and seasonal.

The demand for natural gas and for certain of ONEOK Partners’ businesses’ NGL products, such as propane, is weather sensitive and seasonal, with a portion of revenues derived from sales for heating during the winter months. Weather conditions influence directly the volume of, among other things, natural gas and propane delivered to customers. Deviations in weather from normal levels and the seasonal nature of certain of ONEOK Partners’ businesses can create variations in earnings and short-term cash requirements.

Energy efficiency and technological advances may affect the demand for natural gas and affect adversely ONEOK Partners’ operating results.

More strict local, state and federal energy-conservation measuresreporting in the future or technological advancesthat we will be able to continue to comply with our obligations under Section 404 of the Sarbanes-Oxley Act of 2002. Any failure to maintain effective internal controls, or difficulties encountered in heating, including installationimplementing or improving our internal controls, could harm our operating results or cause us to fail to meet our reporting obligations. Ineffective internal controls could also cause investors to lose confidence in our reported financial information, which would likely have a negative effect on the trading price of improved insulationour equity, our access to capital markets and the developmentcost of more efficient furnaces, energy generationcapital.

Our employees or directors may engage in misconduct or other devicesimproper activities, including noncompliance with regulatory standards and requirements.

As with all companies, we are exposed to the risk of employee fraud or other misconduct. Our Board of Directors has adopted a code of business conduct and ethics that applies to our directors, officers (including our principal executive and financial officers, principal accounting officer, controllers and other persons performing similar functions) and all other employees. We require all directors, officers and employees to adhere to our code of business conduct and ethics in addressing the legal and ethical issues encountered in conducting their work for our company. Our code of business conduct and ethics requires, among other things, that our directors, officers and employees avoid conflicts of interest, comply with all applicable laws and other legal requirements, conduct business in an honest and ethical manner and otherwise act with integrity and in our company’s best interest. All directors, officers and employees are required to report any conduct that they believe to be an actual or apparent violation of our code of business conduct and ethics. However, it is not always possible to identify and deter misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to comply with such laws or regulations. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could affect the demand for natural gas and adversely affect ONEOK Partners’ and our reputation, business, results of operations, financial position and cash flows.


InAn impairment of goodwill, long-lived assets, including intangible assets, and equity-method investments could reduce our earnings.

Goodwill is recorded when the competitionpurchase price of a business exceeds the fair market value of the tangible and separately measurable intangible net assets. GAAP requires us to test goodwill for customers, ONEOK Partnersimpairment on an annual basis or when events or circumstances occur indicating that goodwill might be impaired. Long-lived assets, including intangible assets with finite useful lives, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may have significant levelsnot be recoverable. For the investments we account for under the equity method, the impairment test considers whether the fair value of excess capacity on its natural gasthe equity investment as a whole, not the underlying net assets, has declined and natural gas liquids pipelines, processing, fractionation and storage assets.

ONEOK Partners’ natural gas and natural gas liquids pipelines, processing, fractionation and storage assets compete withwhether that decline is other pipelines, processing, fractionation and storage facilitiesthan temporary. For example, if a low commodity price environment persisted for natural gas and NGL suppliesa prolonged period, it could result in lower volumes delivered to the markets it serves. Asour systems and impairments of our assets or equity-method investments. If we determine that an impairment is indicated, we would be required to take an immediate noncash charge to earnings with a result of competition, at any given time ONEOK Partners may have significant levels of uncontracted or discounted capacitycorrelative effect on its pipelines, processing, fractionationequity and in its storage assets, which could have a material adverse impact on ONEOK Partners’ or our results of operations and cash flows.balance sheet leverage as measured by consolidated debt to total capitalization.



Any reduction in ONEOK Partners’our credit ratings could affect materially and adversely itsour business, financial condition, liquidity and results of operations.operations, financial position and cash flows.


ONEOK Partners’ senior unsecuredOur long-term debt and our commercial paper program have been assigned an investment-grade credit rating of “Baa2”Baa3 and Prime-2,Prime-3, respectively, by Moody’s and “BBB”BBB and A-2, respectively, by S&P. In February 2017, in conjunction with the announcement of the Merger Transaction with ONEOK Partners described in Note B of the Notes to Consolidated Financial Statements in this Annual Report, S&P affirmed ONEOK Partners’ ratings and outlook and Moody’s placed ONEOK Partners’ credit ratings under review for a downgrade. We cannot provide assurance that any of itsour current ratings will remain in effect for any given period of time or that a rating will not be lowered or withdrawn entirely by a rating agency if, in its judgment, circumstances in the future so warrant. Specifically, ifagency. If Moody’s or S&P were to downgrade ONEOK Partners’our long-term debt or our commercial paper rating, particularly below investment grade, itsour borrowing costs would increase, which would affect adversely itsour financial results, and itsour potential pool of investors and funding sources could decrease. Ratings from credit agencies are not recommendations to buy, sell or hold ONEOK Partners’our securities. Each rating should be evaluated independently of any other rating.


An eventHolders of defaultour common stock may require ONEOK Partners to offer to repurchase certain of its senior notesnot receive dividends in the amount identified in guidance, or may impair its ability to access capital.any dividends at all.


The indentures governing ONEOK Partners’ senior notes include an event of default upon the acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of ONEOK Partners’ outstanding senior notes to declare those senior notes immediately due and payable in full. ONEOK PartnersWe may not have sufficient cash each quarter to pay dividends or maintain current or expected levels of dividends. The actual amount of cash we pay in the form of dividends may fluctuate from quarter to quarter and will depend on handvarious factors, some of which are beyond our control, including our working capital needs, our ability to repurchaseborrow, the restrictions contained in our indentures and repay any accelerated senior notes,credit facility, our debt service requirements and the cost of acquisitions, if any. A failure either to pay dividends or to pay dividends at expected levels could result in a loss of investor confidence, reputational damage and a decrease in the value of our stock price.

Our operating cash flows are derived partially from cash distributions we receive from our unconsolidated affiliates.

Our operating cash flows are derived partially from cash distributions we receive from our unconsolidated affiliates, as discussed in Note M of the Notes to Consolidated Financial Statements in this Annual Report. The amount of cash that our unconsolidated affiliates can distribute principally depends upon the amount of cash flows these affiliates generate from their respective operations, which may cause ONEOK Partnersfluctuate from quarter to borrow money under itsquarter. We do not have any direct control over the cash distribution policies of our unconsolidated affiliates. This lack of control may contribute to us not having sufficient available cash each quarter to continue paying dividends at the current levels.

Additionally, the amount of cash that we have available for cash dividends depends primarily upon our cash flows, including working capital borrowings, and is not solely a function of profitability, which will be affected by noncash items such as depreciation, amortization and provisions for asset impairments. As a result, we may be able to pay cash dividends during periods when we record losses and may not be able to pay cash dividends during periods when we record net income.

We are exposed to the credit facilitiesrisk of our customers or seek alternative financing sourcescounterparties, and our credit-risk management may not be adequate to financeprotect against such risk.

We are subject to the repurchasesrisk of loss resulting from nonpayment and/or nonperformance by our customers and repayment. ONEOK Partnerscounterparties. Our customers or counterparties may experience rapid deterioration of their financial condition as a result of changing market conditions, commodity prices or financial difficulties that could also face difficulties accessing capitalimpact their creditworthiness or its borrowing costs could increase, impacting its ability to pay us for our services. We assess the creditworthiness of our customers and counterparties and obtain financingcollateral or contractual terms as we deem appropriate. We cannot, however, predict to what extent our business may be impacted by deteriorating market or financial conditions, including possible declines in our customers’ and counterparties’ creditworthiness. Our customers and counterparties may not perform or adhere to our existing or future contractual arrangements. To the extent our customers and counterparties are in financial distress or commence bankruptcy proceedings, contracts with them may be subject to renegotiation or rejection under applicable provisions of the United States Bankruptcy Code. If our risk-management policies and procedures fail to assess adequately the creditworthiness of existing or future customers and counterparties, any material nonpayment or nonperformance by our customers and counterparties due to inability or unwillingness to perform or adhere to contractual arrangements could affect adversely our business, results of operations, financial position, cash flows and ability to pay cash dividends to our shareholders.

Our primary market areas are located in the Mid-Continent, Rocky Mountain, Permian Basin and Gulf Coast regions of the U.S. Our counterparties are primarily major integrated and independent exploration and production, pipeline, marketing and petrochemical companies. Therefore our counterparties may be similarly affected by changes in economic, regulatory or other factors that may affect our overall credit risk.

Changes in interest rates could affect adversely our business.

We use both fixed and variable rate debt, and we are exposed to market risk due to the floating interest rates on our short-term borrowings. Our results of operations, cash flows and financial position could be affected adversely by significant fluctuations in interest rates from current levels.

In July 2017, the head of the United Kingdom Financial Conduct Authority announced the desire to phase out the use of LIBOR by the end of 2021. In addition, the U.S. Federal Reserve, in conjunction with the Alternative Reference Rates Committee, a steering committee composed of large US financial institutions, is considering replacing U.S. dollar LIBOR with the Secured Overnight Financing Rate (SOFR), a new index supported by short-term Treasury repurchase agreements. Although there have been some issuances utilizing SOFR, it is unknown whether this alternative reference rate will attain market acceptance as a replacement for acquisitions or capital expenditures,LIBOR.


Our $2.5 Billion Credit Agreement and our $1.5 Billion Term Loan Agreement include provisions that grant the agreement’s administrative agents with broad discretion to refinanceestablish a replacement rate for LIBOR, if necessary.

Our indebtedness and to fulfill its debt obligations.

ONEOK Partners’ indebtednessguarantee obligations could impair itsour financial condition and our ability to fulfill itsour obligations.


As of December 31, 2016, ONEOK Partners2019, we had total indebtedness of approximately $7.9$12.8 billion. ItsOur indebtedness and guarantee obligations could have significant consequences. For example, itthey could:
make it more difficult for us to satisfy itsour obligations with respect to its senior notes and other indebtedness due to the increased debt-service obligations, which could, in turn, result in an event of default on such other indebtedness or itsthe senior notes;
impair itsour ability to obtain additional financing in the future for working capital, capital expenditures, acquisitions or general business purposes;
diminish itsour ability to withstand a downturn in itsour business or the economy;
require itus to dedicate a substantial portion of itsour cash flowflows from operations to debt-service payments, thereby reducing the availability of cash for working capital, capital expenditures, acquisitions, distributions to partners anddividends or general partnershipcorporate purposes;
limit itsour flexibility in planning for, or reacting to, changes in itsour business and the industry in which it operates;we operate; and
place itus at a competitive disadvantage compared with itsour competitors that have proportionately less debt.debt and fewer guarantee obligations.


ONEOK Partners isWe are not prohibited under the indentures governing itsthe senior notes from incurring additional indebtedness, but itsour debt agreements do subject itus to certain operational limitations summarized in the next paragraph. ONEOK Partners’ incurrence ofIf we incur significant additional indebtedness, would exacerbateit could worsen the negative consequences mentioned above and could affect adversely itsour ability to repay its senior notes andour other indebtedness.


ONEOK Partners’ debt agreementsOur $2.5 Billion Credit Agreement and $1.5 Billion Term Loan Agreement contain provisions that restrict itsour ability to finance future operations or capital needs or to expand or pursue itsour business activities. For example, certain of these agreements contain provisions that, among other things, limit itsour ability to make loans or investments, make material changes to the nature of itsour business, merge, consolidate or engage in asset sales, grant liens or make negative pledges. Certain agreements also require itus to maintain certain financial ratios, which limit the amount of additional indebtedness itwe can incur. For example, the ONEOK Partners Credit Agreement contains a financial covenant requiring it to maintain a ratio of indebtedness to adjusted EBITDA (EBITDA,incur, as defineddescribed in the ONEOK Partners Credit Agreement, adjusted for all noncash charges“Liquidity and increased for projected EBITDA from certain lender-approved capital expansion projects)Capital Resources” section of no more than 5.0 to 1. If ONEOK Partners consummates one or more acquisitionsPart II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations, in which the aggregate purchase price is $25 million or more, the allowable ratio of indebtedness to adjusted EBITDA will increase to 5.5 to 1 for the quarter in which the acquisition was completed and the two following quarters.


this Annual Report. These restrictions could result in higher costs of borrowing and impair ONEOK Partners’our ability to generate additional cash. Future financing agreements ONEOK Partnerswe may enter into may contain similar or more restrictive covenants.


If ONEOK Partners iswe are unable to meet itsour debt-service obligations itor comply with financial covenants, we could be forced to restructure or refinance itsour indebtedness, seek additional equity capital or sell assets. ItWe may be unable to obtain financing raise equity or sell assets on satisfactory terms, or at all.


Borrowings under the ONEOK Partners Credit AgreementThe right to receive payments on our outstanding debt securities and its senior notes are nonrecoursesubsidiary guarantees is unsecured and will be effectively subordinated to ONEOK,any future secured indebtedness as well as to any existing and ONEOK doesfuture indebtedness of our subsidiaries that do not guarantee the senior notes.

Although many of our operating subsidiaries have guaranteed our debt commercial paper or other similar commitments of ONEOK Partners. Followingsecurities, the completion of the Merger Transaction,guarantees are subject to release under certain circumstances, and we and ONEOK Partners expect to enter into a cross guarantee agreement whereby each party to the agreement unconditionally guarantees and becomes liable for the indebtedness of each other party to the agreement.

ONEOK Partners has adopted certain valuation methodologies in determining a unitholder’s allocations of income, gain, loss and deduction. The IRS may challenge these methodologies or the resulting allocations, and such a challenge could affect adversely the value of ONEOK Partners’ common units.

When ONEOK Partners issues additional units or engages in certain other transactions, ONEOK Partners determines the fair market value of its assets and allocates any unrealized gain or loss attributable to its assets to thecapital accounts of its unitholders and its general partner. ONEOK Partners’ methodology may be viewed as understating the value of its assets.have subsidiaries that are not guarantors. In that case, there maythe debt securities effectively would be a shiftsubordinated to the claims of income, gain, lossall creditors, including trade creditors and deduction between certain unitholders andtort claimants, of our subsidiaries that are not guarantors. In the general partner, which may be unfavorable to such unitholders. Moreover, under ONEOK Partners’ current valuation methods, subsequent purchasers of common units may have a greater portion of their Internal Revenue Code Section 743(b) adjustment allocated to ONEOK Partners’ tangible assets and a lesser portion allocated to ONEOK Partners’ intangible assets. The IRS may challenge ONEOK Partners’ valuation methods or ONEOK Partners’ allocationevent of the Section 743(b) adjustment attributableinsolvency, bankruptcy, liquidation, reorganization, dissolution or winding up of the business of a subsidiary that is not a guarantor, creditors of that subsidiary would generally have the right to ONEOK Partners’ tangible and intangible assets, and allocationsbe paid in full before any distribution is made to us or the holders of income, gain, loss and deduction between the general partner anddebt securities.

An event of default may require us to offer to repurchase certain of ONEOK Partners’ unitholders.

A successful IRS challenge to these methods or allocations could affect adversely the amount, character and timing of taxable income or loss being allocated to ONEOK Partners’ unitholders. It also could affect the amount of gain from ONEOK Partners unitholders’ sale of common units and could have a negative impact on the value of the common units or result in audit adjustments to ONEOK Partners unitholders’ tax returns without the benefit of additional deductions.

ONEOK Partners’ treatment of a purchaser of common units as having the same tax benefits as the seller could be challenged, resulting in a reduction in value of the common units.

Because ONEOK Partners cannot match transferors and transferees of common units, ONEOK Partners is required to maintain the uniformity of the economic and tax characteristics of these units in the hands of the purchasers and sellers of these units. ONEOK Partners does so by adopting certain depreciation conventions that do not conform to all aspects of existing United States Treasury regulations. A successful IRS challenge to these conventions could affect adversely the tax benefits to a unitholder of ownership of the common units and could have a negative impact on their value or result in audit adjustments to ONEOK Partners unitholders’ tax returns.

Increased regulation of exploration and production activities, including hydraulic fracturing and disposal of waste water, could result in reductions or delays in drilling and completing new oil and natural gas wells, which could impact adversely ONEOK Partners’ revenues by decreasing the volumes of unprocessed natural gas and NGLs transported on its or its joint ventures’ natural gas and natural gas liquids pipelines.

The natural gas industry is relying increasingly on natural gas supplies from nonconventional sources, such as shale and tight sands. Natural gas extracted from these sources frequently requires hydraulic fracturing, which involves the pressurized injection of water, sand, and chemicals into the geologic formation to stimulate natural gas production. Recently, there have been initiatives at the federal and state levels to regulate or otherwise restrict the use of hydraulic fracturing or the disposal of waste water used in the hydraulic fracturing process, and several states have adopted regulations that impose more stringent permitting, disclosure and well-completion requirements on hydraulic fracturing operations. Legislation or regulations placing restrictions on hydraulic fracturing activities, including waste-water disposal, could impose operational delays, increased operating costs and additional regulatory burdens on exploration and production operators, which could reduce their production of unprocessed natural gas and, in turn, adversely affect ONEOK Partners’ revenues and results of operations by decreasing the volumes of unprocessed natural gas and NGLs gathered, treated, processed, fractionated and transported on ONEOK Partners’ or its joint ventures’ natural gas and natural gas liquids pipelines, several of which gather unprocessed natural gas and NGLs from areas where the use of hydraulic fracturing is prevalent.


Continued development of new supply sources could impact demand.

The discovery of nonconventional natural gas production areas nearer to certain market areas that ONEOK Partners serves may compete with natural gas originating in production areas connected to ONEOK Partners’ systems. For example, the Marcellus Shale in Pennsylvania, New York, West Virginia and Ohio may cause natural gas in supply areas connected to ONEOK Partners’ systems to be diverted to markets other than its traditional market areas and may affect capacity utilization adversely on ONEOK Partners’ pipeline systemsour and ONEOK Partners’ senior notes or may impair our ability to renew or replace existing contracts at rates sufficient to maintain current revenues and cash flows. In addition, supply volumes from these nonconventional natural gas production areas may compete with and displace volumes from the Mid-Continent, Permian, Rocky Mountains and Canadian supply sources inaccess capital.

The indentures governing certain of our and ONEOK Partners’ markets. Insenior notes include an event of default upon the Natural Gas Gatheringacceleration of other indebtedness of $15 million or more for certain of our senior notes or $100 million or more for certain of our and Processing segment, the development of these new nonconventional reserves could move drilling rigs from ONEOK Partners’ current service areassenior notes. Such events of default would entitle the trustee or the holders of 25% in aggregate principal amount of our and ONEOK Partners’ outstanding senior notes to other areas,declare those senior notes immediately due and payable in full. We may not have sufficient cash on hand to repurchase and repay any accelerated senior notes, which may reduce demandcause us to

borrow money under our credit facility or seek alternative financing sources to finance the repurchases and repayment. We could also face difficulties accessing capital or our borrowing costs could increase, impacting our ability to obtain financing for ONEOK Partners’ services. In the Natural Gas Pipelines segment, the displacement of natural gas originating in supply areas connectedacquisitions or capital expenditures, to ONEOK Partners’ pipeline systems by these new supply sources that are closerrefinance indebtedness and to the end-use markets could result in lower transportation revenues, which could have a material adverse impact on ONEOK Partners’ business, financial condition, results of operations and cash flows.fulfill our debt obligations.


A court may use fraudulent conveyance considerations to avoid or subordinate the Intermediate Partnership’s guaranteecross guarantees of certain ofour and ONEOK Partners’ senior notes.indebtedness.


Various applicable fraudulent conveyance lawsONEOK, ONEOK Partners and the Intermediate Partnership have been enactedcross guarantees in place for the protection of creditors.our and ONEOK Partners’ indebtedness. A court may use fraudulent conveyance laws to subordinate or avoid the guaranteecross guarantees of certain of our and ONEOK Partners’ senior notes issued the Intermediate Partnership.indebtedness. It is also possible that under certain circumstances, a court could hold that the direct obligations of the Intermediate Partnership could be superior to the obligations under that guarantee.

A court could avoid or subordinate the Intermediate Partnership’sguarantor’s guarantee of certain ofour and ONEOK Partners’ senior notesindebtedness in favor of the Intermediate Partnership’sguarantor’s other debts or liabilities to the extent that the court determined either of the following were true at the time the Intermediate Partnershipguarantor issued the guarantee:
the Intermediate Partnershipguarantor incurred the guarantee with the intent to hinder, delay or defraud any of its present or future creditors or the Intermediate Partnershipguarantor contemplated insolvency with a design to favor one or more creditors to the total or partial exclusion of others; or
the Intermediate Partnershipguarantor did not receive fair consideration or reasonable equivalent value for issuing the guarantee and, at the time it issued the guarantee, the Intermediate Partnership:guarantor:
–     was insolvent or rendered insolvent by reason of the issuance of the guarantee;
was engaged or about to engage in a business or transaction for which its remaining assets constituted unreasonably small capital; or
–     intended to incur, or believed that it would incur, debts beyond its ability to pay such debts as they matured.


The measure of insolvency for purposes of the foregoing will vary depending upon the law of the relevant jurisdiction. Generally, however, an entity would be considered insolvent for purposes of the foregoing if:
the sum of its debts, including contingent liabilities, were greater than the fair saleable value of all of its assets at a fair valuation;
the present fair saleable value of its assets was less than the amount that would be required to pay its probable liability on its existing debts, including contingent liabilities, as they become absolute and mature; or
it could not pay its debts as they become due.


Among other things, a legal challenge of the Intermediate Partnership’s guaranteecross guarantees of certain ofour and ONEOK Partners’ senior notesindebtedness on fraudulent conveyance grounds may focus on the benefits, if any, realized by the Intermediate Partnershipguarantor as a result of our and ONEOK Partners’ issuance of such senior notes.debt. To the extent the Intermediate Partnership’sguarantor’s guarantee of certain ofour and ONEOK Partners’ senior notesindebtedness is avoided as a result of fraudulent conveyance or held unenforceable for any other reason, the holders of such senior notesdebt would cease to have any claim in respect of the guarantee.


ONEOK PartnersThe cost of providing pension and postretirement health care benefits to eligible employees and qualified retirees is subject to changes in pension fund values and changing demographics and may be unableincrease.

We have a defined benefit pension plan for certain employees and former employees hired before January 1, 2005, and postretirement welfare plans that provide postretirement medical and life insurance benefits to cause its joint venturescertain employees hired prior to take or not2017 who retire with at least five years of full-time service. The cost of providing these benefits to take certain actions unless some or all of its joint-venture participants agree.

ONEOK Partners participates in several joint ventures. Dueeligible current and former employees is subject to the nature of some of these arrangements, each participant in these joint ventures has made substantial investmentschanges in the joint venturemarket value of our pension and accordingly, has required that the relevant charter documents contain certain features designed to provide each participant with the opportunity to participatepostretirement benefit plan assets, changing demographics, including longer life expectancy of plan participants and their beneficiaries and changes in the management

of the joint ventureour defined benefit pension plan and to protect its investment, as well as any other assets that may be substantially dependent on or otherwise affected by the activities of that joint venture. These participation and protective features customarily include a corporate governance structure that requires at least a majority-in-interest vote to authorize many basic activities and requires a greater voting interest (sometimes up to 100 percent) to authorize more significant activities. Examples of these more significant activities are large expenditures or contractual commitments, the construction or acquisition of assets, borrowing money or otherwise raising capital, transactions with affiliates of a joint-venture participant, litigation and transactions not in the ordinary course of business, among others. Thus, without the concurrence of joint-venture participants with enough voting interests, ONEOK Partners may be unable to cause any of its joint ventures to take or not to take certain actions, even though those actions may be in the best interest of ONEOK Partners or the particular joint venture.

Moreover, any joint-venture owner generally may sell, transfer or otherwise modify its ownership interest in a joint venture, whether in a transaction involving third parties or the other joint-venture owners. Any such transaction could result in ONEOK Partners being required to partner with different or additional parties.

ONEOK Partners’ operating cash flow is derived partially from cash distributions it receives from its unconsolidated affiliates.

ONEOK Partners’ operating cash flow is derived partially from cash distributions it receives from its unconsolidated affiliates, as discussed inpostretirement welfare plans, see Note NK of the Notes to Consolidated Financial Statements. The amountStatements in this Annual Report.

Any sustained declines in equity markets and reductions in bond yields may affect adversely the value of our pension and postretirement benefit plan assets. In these circumstances, additional cash that ONEOK Partners’ unconsolidated affiliates can distribute principally depends upon the amount of cash flow these affiliates generate from their respective operations, which may fluctuate from quartercontributions to quarter. ONEOK Partners does not have any direct control over the cash distribution policies of its unconsolidated affiliates. This lack of control may contribute to ONEOK Partners’ not having sufficient available cash each quarter to continue paying distributions at its current levels.

Additionally, the amount of cash that ONEOK Partners has available for cash distribution depends primarily upon its cash flow, including cash flow from financial reserves and working capital borrowings, and is not solely a function of profitability, which will be affected by noncash items such as depreciation, amortization and provisions for asset impairments. As a result, ONEOK Partnersour pension plans may be able to make cash distributions during periods when it records lossesrequired, which could affect adversely our business, financial condition and may not be able to make cash distributions during periods when it records net income.liquidity.


ITEM 1B.    UNRESOLVED STAFF COMMENTS


Not applicable.


ITEM 2.    PROPERTIES


A description of our and ONEOK Partners’ properties is included in Item 1, Business.

ITEM 3.    LEGAL PROCEEDINGS


Gas Index Pricing Litigation-We, ONEOK Energy Services Company, L.P. (OESC) and one other affiliate are defending, either individually or together, against the following lawsuits that claim damages resulting from the alleged market manipulation or false reporting of prices to gas index publications by us and others: Sinclair Oil Corporation v. ONEOK Energy Services Corporation, L.P., et al. (filedInformation about our legal proceedings is included in the United States District Court for the District of Wyoming in September 2005, transferred to MDL-1566 in the United States District Court for the District of Nevada); Reorganized FLI, Inc. (formerly J.P. Morgan Trust Company) v. ONEOK, Inc., et al. (filed in the District Court of Wyandotte County, Kansas, in October 2005, transferred to MDL-1566 in the United States District Court for the District of Nevada); Learjet, Inc., et al. v. ONEOK, Inc., et al. (filed in the District Court of Wyandotte, Kansas, in November 2005, transferred to MDL-1566 in the United States District Court for the District of Nevada); Arandell Corporation, et al. v. Xcel Energy, Inc., et al. (filed in the Circuit Court for Dane County, Wisconsin, in December 2006, transferred to MDL-1566 in the United States District Court for the District of Nevada); Heartland Regional Medical Center, et al. v. ONEOK, Inc., et al. (filed in the Circuit Court of Buchanan County, Missouri, in March 2007, transferred to MDL-1566 in the United States District Court for the District of Nevada); NewPage Wisconsin System v. CMS Energy Resource Management Company, et al. (filed in the Circuit Court for Wood County, Wisconsin, in March 2009, transferred to MDL-1566 in the United States District Court for the District of Nevada and now consolidated with the Arandell case). The plaintiffs allege that we, OESC and one other affiliate and approximately nine other energy companies and their affiliates engaged in an illegal scheme to inflate natural gas prices by providing false information to gas price index publications. AllNote N of the complaints arise out of a CFTC investigation into and reports concerning false gas price index-reporting or manipulationNotes to Consolidated Financial Statements in the energy marketing industry during the years from 2000 to 2002.this Annual Report.


On July 18, 2011, the trial court granted judgments in favor of ONEOK, Inc., OESC and other unaffiliated entities in the following cases: Reorganized FLI, Learjet, Arandell, Heartland, and NewPage. The court also granted judgment in favor of OESC on all state law claims asserted in the Sinclair case. On August 18, 2011, the trial court entered an order approving a stipulation by the plaintiffs and our affiliate, Kansas Gas Marketing Company (“KGMC”), for a dismissal without prejudice of the plaintiffs’ claims against KGMC in the Learjet and Heartland cases.

On April 10, 2013, the United States Court of Appeals for the Ninth Circuit reversed the summary judgments that had been granted in favor of ONEOK, OESC and other unaffiliated defendants in the following cases: Reorganized FLI, Learjet, Arandell, Heartland and NewPage. The Ninth Circuit also reversed the summary judgment that had been granted in favor of OESC on all state law claims asserted in the Sinclair case. On April 21, 2015, the United States Supreme Court affirmed the decision of the Ninth Circuit. The cases were remanded back to the trial court (the United States District Court for the District of Nevada) for further proceedings.

In November 2016, we settled the claims alleged against us and our affiliate OESC in Reorganized FLI. The amount we paid to settle this case is not material to our results of operations, financial position or cash flows and was paid with cash on hand.

In November 2016, we entered into an agreement to settle the claims alleged against us and our affiliates, OESC and Kansas Gas Marketing Company, in the following cases: Learjet,Arandell,Heartland and NewPage. Our settlement of these cases is pending final approval by the court in MDL-1566. The amount we agreed to pay to settle these cases is not material to our results of operations, financial position or cash flows and is expected to be paid with cash on hand.

The above settlements do not apply to the Sinclair case. We expect that future charges, if any, from the ultimate resolution of this matter will not be material to our results of operations, financial position or cash flows.

Other Legal Proceedings - We and ONEOK Partners are party to various other litigation matters and claims that have arisen in the normal course of our operations. While the results of these various other litigation matters and claims cannot be predicted with certainty, we believe the reasonably possible losses from such matters, individually and in the aggregate, are not material. Additionally, we believe the probable final outcome of such matters will not have a material adverse effect on our consolidated results of operations, financial position or cash flows.


ITEM 4.    MINE SAFETY DISCLOSURES


Not applicable.



PART II


ITEM 5.MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

MARKET INFORMATION AND HOLDERS


Our common stock is listed on the NYSE under the trading symbol “OKE.” The corporate name ONEOK is used in newspaper stock listings. The following table sets forth the high and low closing prices of our common stock for the periods indicated:
  Year Ended
December 31, 2016
 Year Ended
December 31, 2015
  High Low High Low
First Quarter $30.82
 $19.62
 $49.92
 $40.23
Second Quarter $47.45
 $28.37
 $51.07
 $38.83
Third Quarter $51.39
 $42.99
 $41.40
 $30.86
Fourth Quarter $59.03
 $46.44
 $39.58
 $18.93


At February 21, 2017,18, 2020, there were 13,79214,001 holders of record of our 210,757,806413,319,000 outstanding shares of common stock.


DIVIDENDS

The following table sets forth the quarterly dividends declared and paid per share of our common stock during the periods indicated:
  Years Ended December 31,
  2016 2015 2014
First Quarter $0.615
 $0.605
 $0.40
Second Quarter 0.615
 0.605
 0.56
Third Quarter 0.615
 0.605
 0.575
Fourth Quarter 0.615
 0.615
 0.59
Total $2.46
 $2.43
 $2.125

In January 2017, we declared a dividend of $0.615 per share ($2.46 per share on an annualized basis), which was paid on February 14, 2017, to shareholders of record as of January 30, 2017.

EMPLOYEE STOCK AWARD PROGRAM

UnderFor information regarding our Employee Stock Award Program we issued, for no monetary consideration, to all eligible employees one share of our common stock when the per-share closing price of our common stock on the NYSE was for the first time at or above $13 per share, and one additional share of common stock when the per-share closing price of our common stock on the NYSE was at or above each one dollar increment above $13. No shares were issued to employees under this program during 2016 and 2015. Shares issued to employees under this program during 2014 totaled 49,864, andother equity compensation expense related to the Employee Stock Award Plan was $2.1 million.

The total number of shares of our common stock available for issuance under this program is 900,000. The shares issued under this program have not been registered under the Securities Act, in reliance upon the position taken by the SEC (see Release No. 6188, dated February 1, 1980) that the issuance of shares to employees pursuant to a program of this kind does not require registration under the Securities Act. Seeplans see Note KJ of the Notes to Consolidated Financial Statements and “Equity Compensation Plan Information” included in Part III, Item 12, Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters, in this Annual Report for additional information about the employee stock award program and other equity compensation plans.Report.



PERFORMANCE GRAPH


The following performance graph compares the performance of our common stock with the S&P 500 Index, the Alerian MLPMidstream Energy Select Index and a ONEOK Peer Group during the period beginning on December 31, 2011,2014, and ending on December 31, 2016.2019.


The graph assumes a $100 investment in our common stock and in each of the indices at the beginning of the period and a reinvestment of dividends paid on such investments throughout the period.


Value of $100 Investment, Assuming Reinvestment of Distributions/Dividends,
at December 31, 2011,2014, and at the End of Every Year Through December 31, 2016,2019.
in ONEOK, Inc., the S&P 500 Index, the Alerian MLP Index and a ONEOK Peer Group

chart-cde29d5ed2ea3a058d2a01.jpg

 Cumulative Total Return Cumulative Total Return
 Years Ended December 31, Years Ended December 31,
 2012 2013 2014 2015 2016 2015 2016 2017 2018 2019
                    
ONEOK, Inc. $101.54
 $151.99
 $143.88
 $75.67
 $188.35
 $52.64
 $131.26
 $128.53
 $136.60
 $201.86
S&P 500 Index $115.98
 $153.51
 $174.47
 $176.88
 $197.98
 $101.37
 $113.49
 $138.26
 $132.19
 $173.80
ONEOK Peer Group (a) $103.93
 $148.30
 $165.59
 $103.95
 $142.22
 $55.66
 $78.90
 $73.65
 $63.01
 $68.41
Alerian MLP Index (b) $104.83
 $133.76
 $140.13
 $94.56
 $111.69
Alerian Midstream Energy Select Index (b) $62.86
 $90.08
 $90.52
 $74.34
 $90.52
(a) - The ONEOK Peer Group is comprisedcomposed of the following companies: Boardwalk PipelineDCP Midstream, LP; Enable Midstream Partners, LP; BuckeyeEnergy Transfer LP.; EnLink Midstream, LLC; Enterprise Products Partners L.P.; DCP Midstream Partners, L.P; Enbridge Energy Partners, L.P; Energy Transfer Partners, L.P; EnLink Midstream Partners, L.P; EQT Corporation;Kinder Morgan, Inc.; Magellan Midstream Partners, L.P; National Fuel Gas Company;L.P.; MPLX LP; NuStar Energy L.P.; Plains All American Pipeline, L.P.; Spectra Energy Corp.; Targa Resources Corp.; and The Williams Companies, Inc.
(b) - The Alerian MLPMidstream Energy Select Index measures the composite performance of more than 40 of the most prominentapproximately 35 North American energy master limited partnerships.infrastructure companies who are engaged in midstream activities involving energy commodities.



ITEM 6.    SELECTED FINANCIAL DATA


The following table sets forth our selected financial data for each of the periods indicated:
 Years Ended December 31, Years Ended December 31,
 2016 2015 2014 2013 2012 2019 2018 2017 2016 2015
 
(Millions of dollars except per share amounts)
 
(Millions of dollars, except per share data)
Revenues $8,920.9
 $7,763.2
 $12,195.1
 $11,871.9
 $10,184.1
 $10,164.4
 $12,593.2
 $12,173.9
 $8,920.9
 $7,763.2
Income from continuing operations $745.6
 $385.3
 $668.7
 $589.1
 $677.7
Income from continuing operations attributable to ONEOK $354.1
 $251.1
 $319.7
 $278.7
 $294.8
Net income attributable to ONEOK $352.0
 $245.0
 $314.1
 $266.5
 $360.6
Net income $1,278.6
 $1,155.0
 $593.5
 $743.5
 $379.2
Total assets $16,138.8
 $15,446.1
 $15,261.8
 $17,692.2
 $15,857.1
 $21,812.1
 $18,231.7
 $16,845.9
 $16,138.8
 $15,446.1
Long-term debt, including current maturities $8,330.6
 $8,434.2
 $7,160.8
 $7,715.0
 $6,480.8
 $12,487.4
 $9,381.0
 $8,524.3
 $8,330.6
 $8,434.2
Earnings per share - continuing operations  
  
  
  
  
Basic $1.68
 $1.19
 $1.53
 $1.35
 $1.43
Diluted $1.67
 $1.19
 $1.52
 $1.33
 $1.40
Earnings per share - total  
  
  
  
  
        
  
Basic $1.67
 $1.17
 $1.50
 $1.29
 $1.75
 $3.09
 $2.80
 $1.30
 $1.67
 $1.17
Diluted $1.66
 $1.16
 $1.49
 $1.27
 $1.71
 $3.07
 $2.78
 $1.29
 $1.66
 $1.16
Dividends declared per common share $2.46
 $2.43
 $2.125
 $1.48
 $1.27
Dividends declared per share of common stock $3.53
 $3.245
 $2.72
 $2.46
 $2.43


ONEOK PartnersChanges in commodity prices and sales volumes affect both revenue and cost of sales and fuel, and, therefore, the changes in revenue in the above table are largely offset in cost of sales and fuel.

In 2019, we completed underwritten public offerings of $1.25 billion and $2.0 billion senior unsecured notes in March and August, respectively, primarily to fund our capital-growth projects.

Upon adoption of Topic 606 in January 2018, we determined that certain Natural Gas Gathering and Processing segment POP with fee contracts and Natural Gas Liquids segment exchange services contracts that include the purchase of commodities are supplier contracts. Contractual fees in these identified contracts are recorded as a reduction of the commodity purchase price in cost of sales and fuel. In 2017 and prior periods, these fees were recorded as services revenue.

In the fourth quarter 2017, we recorded a one-time noncash charge to net income through income tax expense of $141.3 million, related to the revaluation of our deferred tax balances and a valuation allowance on certain state net operating loss and tax credit carryforwards resulting from the enactment of the Tax Cuts and Jobs Act. For more information, see Note L in the Notes to the Consolidated Financial Statements in this Annual Report.

Also in 2017, we incurred a $20.0 million noncash expense related to our Series E Preferred Stock contribution to the Foundation and operating costs related to the Merger Transaction of $30.0 million.

We recorded noncash impairment charges of $20.2 million and $264.3 million in 2017 and $76.4 million in 2015, and 2014, respectively.


ITEM 7.MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS


The following discussion and analysis should be read in conjunction with Part I, Item 1, Business, our audited Consolidated Financial Statements and the Notes to Consolidated Financial Statements in this Annual Report.


RECENT DEVELOPMENTS


On January 31, 2017, wePlease refer to the “Financial Results and ONEOK Partners entered into the Merger Agreement, byOperating Information” and among ONEOK, Merger Sub, ONEOK Partners“Liquidity and ONEOK Partners GP, the general partnerCapital Resources” sections of ONEOK Partners, pursuant to which we will acquire allManagement’s Discussion and Analysis of the outstanding common units representing limited partner interests in ONEOK Partners not already directly or indirectly owned by us. Upon the termsFinancial Condition and conditions set forth in the Merger Agreement, Merger Sub will be merged with and into ONEOK Partners, with ONEOK Partners continuing as the surviving entity and as a wholly owned subsidiaryResults of ours, in a taxable transaction to ONEOK Partners’ unitholders. For additional information on this transaction, see Note B of the Notes to Consolidated Financial StatementsOperations in this Annual Report.Report for additional information.


ONEOK and its subsidiaries own all of the general partner interest and certain limited partner interests, which, together, represented a 41.2 percent ownership interest at December 31, 2016,Market Conditions - Volumes increased across our system in ONEOK Partners, one of the largest publicly traded master limited partnerships. ONEOK Partners operates predominantly fee-based businesses in each of its three reportable segments, and its consolidated earnings were approximately 88 percent fee-based in 2016. We continue to expect demand for midstream services and infrastructure development to be primarily driven by producers who need to connect production with end-use markets where current infrastructure is insufficient or nonexistent. We also expect additional demand for ONEOK Partners’ services to support increased demand for NGL products from the petrochemical industry and NGL exporters and increased demand for natural gas from power plants previously fueled by coal and natural gas exports to Mexico.

STACK and SCOOP Opportunity - We expect each of the business segments to benefit from increasing producer activity in the Mid-Continent from the highly productive STACK and SCOOP areas, where there was an increase in producer activity in late 2016, which we expect to continue in 2017. ONEOK Partners has a strong presence in the region, with the Natural Gas Liquids segment’s gathering system serving as a primary NGL takeaway provider through connections to more than 100 third-party natural gas processing plants, theour Natural Gas Gathering and Processing segment’s substantial acreage dedications in some of the most productive areas and the Natural Gas Pipelines segment’s broad footprint. As producers continueLiquids segments in 2019, compared with 2018, which resulted in higher fee-based earnings, primarily as a result of our completed capital-growth projects, continued drilling and producer improvements in production due to developenhanced completion techniques, offset partially by natural production declines.

We experienced fluctuating NGL location price differentials due to increased supply, increased demand in the STACKMid-Continent region, infrastructure constraints and SCOOP areas, weslower demand growth in the Gulf Coast due primarily to delays in the startup of petrochemical facilities and constrained NGL export facilities. The Conway-to-Mont Belvieu OPIS price differential for ethane in ethane/propane mix averaged $0.07 per gallon in 2019, compared with $0.15 per gallon in 2018, which resulted in lower

earnings from our optimization and marketing activities in our Natural Gas Liquids segment. We expect narrower NGL location price differentials in 2020.

Ethane Opportunity - Ethane volumes under long-term contracts delivered to our NGL system averaged 385 MBbl/d in 2019, compared with 380 MBbl/d in 2018, and have generally been increasing since 2017, primarily as a result of NGL demand increasing from exports and petrochemical companies completing ethylene production projects and plant expansions. Our NGL capital-growth projects are expected to help alleviate system constraints, enabling additional NGLs, including ethane, to reach the Mont Belvieu, Texas, market center.

Northern Border Pipeline, which provides key natural gas and NGL volumes to increase in 2017, compared with 2016 volumes, and increased demand for ONEOK Partners’ services from producers that need incremental takeaway capacity for natural gas and NGLs out of the region.


Ethane Opportunity - Ethane rejection levels bythe residue natural gas processors deliveringit receives in order to ONEOK Partners’meet downstream pipeline specifications. When these restrictions take effect, natural gas liquids gathering system have continued to fluctuate and averaged approximately 175 MBbl/d during 2016, primarily in the Mid-Continent region. We expect ethane rejection levels to continue to fluctuate in 2017 as the market begins to balance ethane supply and demand and with changes in the price differentials between ethane and natural gas. We expect ethane recovery levels to increase as ethylene producers and NGL exporters increase their capacity to consume and export additional ethane feedstock volumes. Ethane demand is expected to ramp up as new world-scale ethylene production projects, petrochemical plant modifications, plant expansions and export facilities near completion and begin coming on line in 2017. We expect increases in future ethane recoveries to have a favorable impact on ONEOK Partners’ financial results, beginning primarily in the second half of 2017.

Growth Projects - ONEOK Partners completed its Bear Creek natural gas processing plant and related infrastructure projects in August 2016. These projects expand ONEOK Partners’ natural gas gathering and processing and natural gas liquids gathering infrastructureprocessors in the Williston Basin may recover incremental ethane into the NGL stream in order to capturelower the Btu content of the residue natural gas from new wells and natural gas previously flared by producers.delivered to Northern Border Pipeline. As a result, ethane deliveries to our NGL system may increase.

Growth Projects - Our announced large capital-growth projects that have recently been completed or are currently under construction are outlined in the tables below:
ProjectScope
Approximate
Costs (a)
Expected
Completion
Natural Gas Gathering and Processing
(In millions)
Demicks Lake I plant and related infrastructure200 MMcf/d processing plant and related gathering infrastructure in the core of the Williston Basin$400
Completed
October 2019
Supported by acreage dedications with long-term primarily fee-based contracts
Demicks Lake II plant and related infrastructure200 MMcf/d processing plant and related gathering infrastructure in the core of the Williston Basin$410
Completed
January 2020
Supported by acreage dedications with long-term primarily fee-based contracts
Bear Creek plant expansion and related infrastructure200 MMcf/d processing plant expansion and related gathering infrastructure in the Williston Basin$405First Quarter 2021
Supported by acreage dedications with long-term primarily fee-based contracts
Demicks Lake III plant and related infrastructure200 MMcf/d processing plant and related gathering infrastructure in the core of the Williston Basin$305Third Quarter 2021
Supported by acreage dedications with primarily fee-based contracts
(a) - Excludes capitalized interest/AFUDC.

ProjectScope
Approximate
Costs (a)
Expected
Completion
Natural Gas Liquids
Elk Creek pipeline and related infrastructure900-mile NGL pipeline from the Williston Basin to the Mid-Continent region, with capacity of up to 240 MBbl/d, and related infrastructure$1,400
Completed
December 2019 (b)
Anchored by long-term contracts
Expansion capability up to 400 MBbl/d with additional pump facilities
Arbuckle II pipeline and related infrastructure530-mile NGL pipeline from the STACK area to Mont Belvieu, Texas, with initial capacity up to approximately 400 MBbl/d, and related infrastructure$1,360First Quarter 2020
Supported by long-term contracts
Expansion capability up to 1 MMBbl/d
West Texas LPG pipeline expansion and Arbuckle II connectionIncreasing mainline capacity by 80 MBbl/d with additional pump facilities and pipeline looping$295First Quarter 2020
Connecting West Texas LPG pipeline system to the Arbuckle II pipeline
Supported by long-term dedicated production from six third-party processing plants expected to produce up to 60 MBbl/d
MB-4 fractionator and related infrastructure125 MBbl/d NGL fractionator in Mont Belvieu, Texas, and related infrastructure, which includes additional NGL storage in Mont Belvieu$575First Quarter 2020 (c)
Fully contracted with long-term contracts
Bakken NGL pipeline extension75-mile NGL pipeline in the Williston Basin connecting to a third-party processing plant$100Fourth Quarter 2020
Supported by a long-term contract with a minimum volume commitment
Arbuckle II extension project and additional gathering infrastructureProvide additional takeaway capacity in the STACK area$240First Quarter 2021
Allow increasing volumes on the Elk Creek pipeline access to fractionation capacity at Mont Belvieu, Texas
Arbuckle II pipeline expansionIncreasing mainline capacity with additional pump facilities$60First Quarter 2021
Increases capacity to 500 MBbl/d
MB-5 fractionator and related infrastructure125 MBbl/d NGL fractionator in Mont Belvieu, Texas, and related infrastructure, which includes additional NGL storage in Mont Belvieu$750First Quarter 2021
Fully contracted with long-term contracts
West Texas LPG pipeline expansionIncreasing mainline capacity by 40 MBbl/d$145First Quarter 2021
Supported by long-term dedicated production from third-party processing plants expected to produce up to 45 MBbl/d
Mid-Continent fractionation facility expansions65 MBbl/d of expansions at our Mid-Continent NGL facilities$150First Quarter 2021 (d)
West Texas LPG pipeline expansionIncreasing mainline capacity by 100 MBbl/d$310Second Quarter 2021
Fully contracted with long-term dedicated production from third-party processing plants
Elk Creek pipeline expansionIncreasing mainline capacity to 400 MBbl/d with additional pump facilities$305Third Quarter 2021 (e)
Supported by long-term dedicated production from ONEOK and third-party processing plants
(a) - Excludes capitalized interest/AFUDC.
(b) - In July 2019, we completed the Natural Gas Pipelines segment, Phase Isouthern section of the Roadrunner pipeline wasfrom the Powder River Basin to our existing Mid-Continent NGL facilities. In December 2019, we completed the northern section of the pipeline from the Williston Basin to the Powder River Basin.
(c) - We completed 75 MBbl/d in December 2019, with the remaining 50 MBbl/d to be completed in March 2016. Phase IIthe first quarter 2020.
(d) - We expect to complete 15 MBbl/d in the third quarter 2020, with the remaining 50 MBbl/d expected to be completed in the first quarter 2021.
(e) - We expect a portion of this incremental capacity to be available as early as first quarter 2021.

Debt Issuances and Repayments - In August 2019, we completed an underwritten public offering of $2.0 billion senior unsecured notes consisting of $500 million,2.75% senior notes due 2024; $750 million, 3.4% senior notes due 2029; and$750 million,4.45% senior notes due 2049. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $1.97 billion and were used for general corporate purposes, including funding of capital expenditures and repayment of existing indebtedness. Repayments included the Roadrunner pipelineredemption of our $300 million, 3.8% senior notes due March

2020 at a redemption price of $308 million in September 2019 and the WesTex pipeline expansion projectrepayment of $250 million of our $1.5 Billion Term Loan agreement in August 2019.

In March 2019, we completed an underwritten public offering of $1.25 billion senior unsecured notes consisting of $700 million, 4.35% senior notes due 2029 and an additional issuance of $550 million of our existing 5.2% senior notes due 2048. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, and exclusive of accrued interest, were completed$1.23 billion. During the six months ended June 30, 2019, we drew the remaining $950 million under our $1.5 Billion Term Loan Agreement. The proceeds were used for general corporate purposes, including repayment of existing indebtedness and funding capital expenditures.

Also, in October 2016, aheadMarch 2019, we repaid our $500 million, 8.625% senior notes at maturity with a combination of original schedulecash on hand and below cost estimates. The Roadrunner pipeline transports natural gas from the Permian Basin in West Texas to the Mexican border near El Paso, Texas, and together with ONEOK Partners’ WesTex intrastate natural gas transmission pipeline, creates a platform for future opportunities to deliver natural gas supply to Mexico. The execution of these capital investments aligns with ONEOK Partners’ strategy to generate consistent growth and sustainable earnings through long-term fee-based projects. ONEOK Partners’ contractual commitments from crude oil and natural gas producers, natural gas processors and electric generators are expected to provide incremental cash flows and long-term fee-based earnings.short-term borrowings.


Change in Presentation of Financial Results Dividends-Our chief operating decision-maker reviews the financial performance of each of ONEOK Partners’ three segments, as well as our financial performance, on a regular basis. Beginning in 2016, adjusted EBITDA by segment is utilized in this evaluation. We believe this financial measure is useful to investors because it and similar measures are used by many companies in our industry as a measurement of financial performance and are commonly employed by financial analysts and others to evaluate our financial performance and to compare financial performance among companies in our industry. See reconciliation of net income to adjusted EBITDA in the “Adjusted EBITDA” section.

Dividends/Distributions -During 2016,2019, we paid dividends totaling $2.46$3.53 per share, which is an increase of 9% from the $2.43$3.245 per share paid in 2015. We declared2018. In February 2020, we paid a quarterly dividend of $0.615$0.935 per share ($2.463.74 per share on an annualized basis), an increase of 9% compared with the same quarter in January 2017, whichthe prior year. Our dividend growth is unchangeddue to the increase in cash flows resulting from the quarterly dividend declared in January 2016. ONEOK Partners’ structure as a master limited partnership requires it to pay out allcontinued growth of its available cash, as defined in the Partnership Agreement, in distributions to its unitholders. During 2016, ONEOK Partners paid cash distributions of $3.16 per unit, which is unchanged from 2015. ONEOK Partners paid total cash distributions to us in 2016 of $790.0 million, which includes $361.2 million from our limited-partner interest and $428.8 million from our general-partner interest, which includes our incentive distribution rights. ONEOK Partners paid a cash distribution of $0.79 per unit ($3.16 per unit on an annualized basis) for the fourth quarter 2016.operations.



FINANCIAL RESULTS AND OPERATING INFORMATION


Consolidated Operations


Selected Financial Results-The following table sets forth certain selected consolidated financial results for the periods indicated:
    Variances Variances
  Years Ended December 31, 2016 vs. 2015 2015 vs. 2014
Financial Results 2016 2015 2014 Increase (Decrease) Increase (Decrease)
  
(Millions of dollars)
Revenues              
Commodity sales $6,858.5
 $6,098.3
 $10,725.0
 $760.2
 12 % $(4,626.7) (43)%
Services 2,062.4
 1,665.0
 1,470.1
 397.4
 24 % 194.9
 13 %
Total revenues 8,920.9
 7,763.3
 12,195.1
 1,157.6
 15 % (4,431.8) (36)%
Cost of sales and fuel (exclusive of items shown separately below) 6,496.1
 5,641.1
 10,088.5
 855.0
 15 % (4,447.4) (44)%
Operating costs 757.1
 693.3
 674.9
 63.8
 9 % 18.4
 3 %
Depreciation and amortization 391.6
 354.6
 294.7
 37.0
 10 % 59.9
 20 %
Impairment of long-lived assets 
 83.7
 
 (83.7) (100)% 83.7
 *
Gain on sale of assets (9.6) (5.6) (6.6) 4.0
 71 % (1.0) (15)%
Operating income $1,285.7
 $996.2
 $1,143.6
 $289.5
 29 % $(147.4) (13)%
Equity in net earnings from investments $139.7
 $125.3
 $117.4
 $14.4
 11 % $7.9
 7 %
Impairment of equity investments $
 $(180.6) $(76.4) $(180.6) (100)% $104.2
 *
Interest expense, net of capitalized earnings $(469.7) $(416.8) $(356.2) $52.9
 13 % $60.6
 17 %
Income from continuing operations $745.6
 $385.3
 $668.7
 $360.3
 94 % $(283.4) (42)%
Income (loss) from discontinued operations, net of tax $(2.1) $(6.1) $(5.6) $4.0
 66 % $(0.5) (9)%
Net income attributable to noncontrolling interests $391.5
 $134.2
 $349.0
 $257.3
 *
 $(214.8) (62)%
Net income attributable to ONEOK $352.0
 $245.0
 $314.1
 $107.0
 44 % $(69.1) (22)%
Adjusted EBITDA $1,828.7
 $1,560.3
 $1,526.8
 $268.4
 17 % $33.5
 2 %
Capital expenditures $624.6
 $1,188.3
 $1,779.2
 $(563.7) (47)% $(590.9) (33)%
* Percentage change is greater than 100 percent or is not meaningful.
        Variances
  Years Ended December 31, 2019 vs. 2018 2018 vs. 2017
Financial Results 2019 2018 2017 Increase (Decrease)
  
(Millions of dollars)
Revenues          
Commodity sales $8,916.1
 $11,395.6
 $9,862.7
 $(2,479.5) $1,532.9
Services 1,248.3
 1,197.6
 2,311.2
 50.7
 (1,113.6)
Total revenues 10,164.4
 12,593.2
 12,173.9
 (2,428.8) 419.3
Cost of sales and fuel (exclusive of items shown separately below) 6,788.0
 9,422.7
 9,538.0
 (2,634.7) (115.3)
Operating costs 982.9
 907.0
 822.7
 75.9
 84.3
Depreciation and amortization 476.5
 428.6
 406.3
 47.9
 22.3
Impairment of long-lived assets 
 
 16.0
 
 (16.0)
(Gain) loss on sale of assets 2.6
 (0.6) (0.9) (3.2) (0.3)
Operating income $1,914.4
 $1,835.5
 $1,391.8
 $78.9
 $443.7
Equity in net earnings from investments $154.5
 $158.4
 $159.3
 $(3.9) $(0.9)
Impairment of equity investments $
 $
 $(4.3) $
 $(4.3)
Interest expense, net of capitalized interest $(491.8) $(469.6) $(485.7) $22.2
 $(16.1)
Net income $1,278.6
 $1,155.0
 $593.5
 $123.6
 $561.5
Adjusted EBITDA $2,580.2
 $2,447.5
 $1,986.9
 $132.7
 $460.6
Capital expenditures $3,848.3
 $2,141.5
 $512.4
 $1,706.8
 $1,629.1
See reconciliation of net income to adjusted EBITDA in the “Adjusted EBITDA” section.


Due to the nature of ONEOK Partners’ contracts, changesChanges in commodity prices and sales volumes affect both commodity salesrevenues and cost of sales and fuel in our Consolidated Statements of Income, and, therefore, the impact is largely offset between the twothese line items.


20162019 vs. 20152018 - Operating income increased due primarily to higher natural gas and NGL volumes from completed capital-growth projects in the Natural Gas Gathering and Processing and Natural Gas Liquids segments and new plant connections and increased ethane recovery in the Natural Gas Liquids segment, higher fees resulting from contract restructuring in the Natural Gas Gathering and Processing segment and higher firm demand charge volumes contracted in the Natural Gas Pipelines segment. These increases were offset partially by lower net realized NGL and natural gas prices in the Natural Gas Gathering and Processing segment, higher depreciation expense due to projects completed in 2016 and 2015, higher labor costs associated with the growth of operations in the Natural Gas Gathering and Processing segment and higher employee-related costs associated with incentive and medical benefit plans and noncash expenses of a share-based deferred compensation plan due primarily to the increase of ONEOK’s share price in 2016.

Equity in net earnings from investments increased due primarily to higher volumes delivered to Overland Pass Pipeline from ONEOK Partners’ Bakken NGL Pipeline and higher firm transportation revenues on Northern Border Pipeline and Roadrunner, offset partially by lower equity earnings from ONEOK Partners’ Powder River Basin equity investments.

Interest expense increased primarily as a result of higher interest costs incurred associated with our $500 million debt issuance in August 2015 and lower capitalized interest due to lower spending on capital-growth projects.the following:
Natural Gas Gathering and Processing - an increase of $95.5 million due primarily to natural gas volume growth, offset partially by a decrease of $20.9 million due primarily to lower realized NGL and natural gas prices, net of hedges;

Natural Gas Liquids - an increase of $148.1 million in exchange services due primarily to higher volumes and average fee rates, offset partially by a decrease of $60.2 million in optimization and marketing due primarily to wider location price differentials in the prior year; and
Natural Gas Pipelines - an increase of $56.5 million from higher transportation services, offset partially by a decrease of $9.1 million from lower net retained fuel and timing of equity gas sales; offset partially by

Net income attributable to noncontrolling interests, which reflects primarily the portion of ONEOK Partners that we do not own, increased$75.9 million in 2016, compared with 2015,operating costs due primarily to higher earnings at ONEOK Partners, including noncash impairment charges in 2015 discussed below.

Adjusted EBITDA increased due primarily to higher natural gas and NGL volumes from completed capital-growth projects in the Natural Gas Gathering and Processing and Natural Gas Liquids segments and new plant connections and increased ethane recovery in the Natural Gas Liquids segment, higher fees resulting from contract restructuring in the Natural Gas Gathering and Processing segment and higher firm demand charge volumes contracted in the Natural Gas Pipelines segment. These increases were offset partially by lower net realized NGL and natural gas prices in the Natural Gas Gathering and Processing segment, higher labor costs associated with the growth of operations in the Natural Gas Gathering and Processing segment and higher employee-related costs associated with incentivelabor and medical benefit plans.

Capital expenditures decreasedbenefits, spending on routine maintenance projects and ad valorem taxes due to the growth of our operations; and
an increase of $47.9 million in depreciation expense due to capital projects placed in serviceservice.

Net income increased for the year ended December 31, 2019, compared with the same period in 2016 and 2015, spending reductions to align with customer needs and lower well connect activities in the Natural Gas Gathering and Processing segment due to a reduction in drilling and completion activity.

2015 vs. 2014 - Operating income decreased2018, due to the sharp decline in commodity prices that began in the fourth quarter 2014items discussed above and continued throughout 2015. ONEOK Partners experienced higher propane and natural gas prices, as well as wider NGL location and product price differentials in the first quarter 2014 as a result of unusually high weather-related seasonal demand. The impact from the price decrease wasallowance for equity funds used during construction related to our capital-growth projects, offset partially by the increasehigher interest expense related to our underwritten public debt offerings in higher gatheredMarch and processed volumes in the Natural Gas Gathering and Processing segment and higher NGL volumes transported on gathering lines and fractionated in the Natural Gas Liquids segment. Operating costs and depreciation and amortization expenseAugust 2019.

Capital expenditures increased due primarily to the growth of operations related to the completedspending on our announced capital-growth projects, including acquisitions, in the Natural Gas Gathering and Processing and Natural Gas Liquids segments. This increase was offset partially by decreased operating costs due to lower rates charged by service providers.projects.

Equity in net earnings from investments increased due primarily to higher volumes in 2015 delivered to Overland Pass Pipeline from the Bakken NGL Pipeline in the Natural Gas Liquids segment.

Interest expense increased primarily as a result of higher interest costs incurred associated with ONEOK Partners’ issuance of $800 million of senior notes in March 2015, higher interest rates on short-term borrowings, lower capitalized interest due to capital-growth projects completed and placed in service in 2014, and higher interest costs incurred associated with our $500 million debt issuance in August 2015.

Income from continuing operations decreased in 2015, compared with 2014, due primarily to the factors discussed above and a $26.4 million net reduction in deferred income tax expense in the first quarter 2014 as a result of the separation of our former natural gas distribution business and the wind down of the energy services business.

Net income attributable to noncontrolling interests, which reflects primarily the portion of ONEOK Partners that we do not own, decreased in 2015, compared with 2014, due primarily to lower earnings at ONEOK Partners, including the noncash impairment charges discussed below.

Capital expenditures decreased due to the completion of several large capital-growth projects in 2014, suspension of several projects and the timing of expenditures in 2015 for ONEOK Partners’ capital-growth projects. Cash paid for acquisitions in 2014 related primarily to the West Texas LPG acquisition for approximately $800 million.

Adjusted EBITDA was relatively unchanged due to higher gathered and processed volumes in the Natural Gas Gathering and Processing segment and higher NGL volumes transported on gathering lines and fractionated in the Natural Gas Liquids segment and higher equity in net earnings from investments due primarily to higher volumes in 2015 delivered to Overland Pass Pipeline from the Bakken NGL Pipeline in the Natural Gas Liquids segment, offset partially by the sharp decline in commodity prices discussed above and higher operating costs due primarily to ad valorem taxes, outside services and employee-related costs resulting from the growth of operations.

ONEOK Partners recorded $264.3 million and $76.4 million of noncash impairment charges, primarily related to its long-lived assets and equity investments in the dry natural gas area of the Powder River Basin in 2015 and 2014, respectively.


Additional information regarding theour financial results and operating information is provided in the following discussiondiscussions for each of theour segments.


Selected Financial Results and Operating Information the Year Ended December 31, 2018 vs. 2017 - The consolidated and segment financial results and operating information for the year ended December 31, 2018, compared with the year ended December 31, 2017, are included in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations of our 2018 Annual Report on Form 10-K, which is available via the SEC’s website at www.sec.gov and our website at www.oneok.com.


Natural Gas Gathering and Processing


Growth Projects - TheOur Natural Gas Gathering and Processing segment is investing in growth projects in NGL-rich areas including the Bakken Shale and Three Forks formations in the Williston Basin and the STACK and SCOOP areas of the Anadarko Basin, that ONEOK Partners expectswe expect will enable itus to meet the needs of crude oil and natural gas producers in those areas. Nearly allSee “Growth Projects” in the “Recent Developments” section for discussion of the new natural gas production is from horizontally drilled wells in nonconventional resource areas. These wells tend to produce volumes at higher initial production rates resulting generally in higher initial decline rates than conventional vertical wells; however, the decline rates flatten out over time. These wells are expected to have long productive lives.our announced capital-growth projects.

In 2015 and 2016, ONEOK Partners completed the following projects:
Completed ProjectsLocationCapacity
Approximate
Costs (a)
Completion Date
(In millions)
Rocky Mountain Region
Lonesome Creek processing plant and infrastructureWilliston Basin200 MMcf/d$600November 2015
Sage Creek infrastructurePowder River BasinVarious$35December 2015
Natural gas compressionWilliston Basin100 MMcf/d$75December 2015
Bear Creek processing plant and infrastructureWilliston Basin80 MMcf/d$240August 2016
Stateline de-ethanizersWilliston Basin26 MBbl/d$85September 2016
(a) Excludes capitalized interest.


For a discussion of ONEOK Partners’our capital expenditure financing, see “Capital Expenditures” in the “Liquidity and Capital Resources” section.


Selected Financial Results and Operating Information-The following tables set forth certain selected financial results and operating information for theour Natural Gas Gathering and Processing segment for the periods indicated:
      Variances Variances
  Years Ended December 31, 2016 vs. 2015 2015 vs. 2014
Financial Results 2016 2015 2014 Increase (Decrease) Increase (Decrease)
  
(Millions of dollars)
NGL sales $586.0
 $554.3
 $1,434.4
 $31.7
 6 % $(880.1) (61)%
Condensate sales 58.3
 55.1
 110.8
 3.2
 6 % (55.7) (50)%
Residue natural gas sales 690.6
 839.5
 1,140.5
 (148.9) (18)% (301.0) (26)%
Gathering, compression, dehydration and processing fees and other revenue 716.7
 388.2
 281.9
 328.5
 85 % 106.3
 38 %
Cost of sales and fuel (exclusive of depreciation and items shown separately below) (1,331.5) (1,265.6) (2,305.7) 65.9
 5 % (1,040.1) (45)%
Operating costs (285.6) (272.4) (257.7) 13.2
 5 % 14.7
 6 %
Equity in net earnings from investments 10.7
 17.9
 20.3
 (7.2) (40)% (2.4) (12)%
Other 1.6
 1.6
 0.7
 
  % 0.9
 *
Adjusted EBITDA $446.8
 $318.6
 $425.2
 $128.2
 40 % $(106.6) (25)%
Impairment of equity investments $
 $(180.6) $(76.4) $(180.6) 100 % $104.2
 *
Capital expenditures $410.5
 $887.9
 $898.9
 $(477.4) (54)% $(11.0) (1)%
* Percentage change is greater than 100 percent.
        Variances
  Years Ended December 31, 2019 vs. 2018 2018 vs. 2017
Financial Results 2019 2018 2017 Increase (Decrease)
  
(Millions of dollars)
NGL sales $1,024.3
 $1,567.2
 $1,208.0
 $(542.9) $359.2
Condensate sales 200.1
 208.8
 103.2
 (8.7) 105.6
Residue natural gas sales 966.1
 1,084.2
 856.3
 (118.1) 227.9
Gathering, compression, dehydration and processing fees and other revenue 178.1
 174.4
 859.1
 3.7
 (684.7)
Cost of sales and fuel (exclusive of depreciation and operating costs) (1,302.3) (2,041.4) (2,216.4) (739.1) (175.0)
Operating costs, excluding noncash compensation adjustments (352.8) (357.7) (302.6) (4.9) 55.1
Equity in net earnings (loss) from investments, excluding noncash impairment charges (6.3) 0.4
 12.1
 (6.7) (11.7)
Other (4.5) (4.3) (1.2) (0.2) (3.1)
Adjusted EBITDA $702.7
 $631.6
 $518.5
 $71.1
 $113.1
Impairment of equity investments $
 $
 $(4.3) $
 $(4.3)
Capital expenditures $926.5
 $694.6
 $284.2
 $231.9
 $410.4
See reconciliation of net income to adjusted EBITDA in the “Adjusted EBITDA” section.


Due to the nature of ONEOK Partners’ contracts, changesChanges in commodity prices and sales volumes affect commodity salesboth revenue and cost of sales and fuel, and, therefore, the impact is largely offset between these line items.

20162019 vs. 20152018 - Adjusted EBITDA increased $128.2$71.1 million, primarily as a result of the following:
an increase of $144.3 million due primarily to restructured contracts resulting in higher fee revenues from increased average fee rates, offset partially by a lower percentage of proceeds retained from the sale of commodities under POP with fee contracts;

an increase of $92.2$95.5 million due primarily to natural gas volume growth in the Rocky Mountain region,Williston Basin and STACK and SCOOP areas, offset partially by volume declinesnatural production declines; and
a decrease of $4.9 million in operating costs due primarily to lower outside services and materials and supplies, offset partially by higher employee-related costs and ad valorem taxes due primarily to the Mid-Continent region and the impactgrowth of weather in the Williston Basin in December 2016; and
an increase of $8.0 million due to contract settlements;our operations; offset partially by
a decrease of $91.9$20.9 million due primarily to lower net realized NGL and natural gas prices;
an increaseprices, net of $13.2 million in operating costs due primarily to increased labor related to the growth of operations resulting from completed capital-growth projects and higher employee-related costs associated with incentive and medical benefit plans;
a decrease of $7.2 million due to lower equity earnings primarily related to ONEOK Partners’ Powder River Basin equity investments;hedges; and
a decrease of $4.0 million due primarily to increased ethane recovery to maintain downstream NGL product specifications.

Capital expenditures decreased due to projects placed in service, spending reductions to align with customer needs and lower well connect activities due to a reduction in drilling and completion activity.

See “Capital Expenditures” in “Liquidity and Capital Resources” for additional detail of ONEOK Partners’ projected capital expenditures.

2015 vs. 2014 - Adjusted EBITDA decreased $106.6 million, primarily as a result of the following:
a decrease of $209.7$6.7 million due primarily to lower equity in net realized NGL, natural gas and condensate prices;
an increase of $14.7 million in operating costs due primarily to higher outside service costs, ad valorem taxes and employee-related costsearnings from investments due to higher labor and employee benefit costs resulting from the growth of operations, offset partially by a decrease in materials and supplies due primarily to lower chemical costs; and
a decrease of $10.4 million due primarily to increased ethane recovery to maintain downstream NGL product specifications; offset partially by
an increase of $91.6 million due primarily to restructured contracts resulting in higher average fee rates and a lower percentage of proceeds retained from the sale of commodities under POP with fee contracts; and
an increase of $38.1 million due primarily to natural gas volume growth in the Rocky Mountain region, offset partially by unplanned operational outages in the Rocky Mountain region and decreased natural gassupply volumes in the Mid Continent region.

Capital expenditures decreased due primarily to the timing of ONEOK Partners’ growth projects and spending reductions to align with customer needs.

ONEOK Partners recorded $254.3 million and $76.4 million of noncash impairment charges primarily related to its long-lived assets and equity investments in the dry natural gas area of the Powder River Basin in 2015 and 2014, respectively. See additional discussion in “Impairment Charges” below.Basin.


Capital expenditures increased due primarily to spending on our announced capital-growth projects.

 Years Ended December 31, Years Ended December 31,
Operating Information (a) 2016 2015 2014 2019 2018 2017
Natural gas gathered (BBtu/d)
 2,034
 1,932
 1,733
 2,753
 2,546
 2,211
Natural gas processed (BBtu/d) (b)
 1,882
 1,687
 1,534
 2,555
 2,382
 2,056
NGL sales (MBbl/d)
 156
 129
 104
 224
 198
 187
Residue natural gas sales (BBtu/d)(b)
 865
 853
 714
 1,201
 1,088
 896
Realized composite NGL net sales price ($/gallon) (c) (d)
 $0.23
 $0.34
 $0.93
Realized condensate net sales price ($/Bbl) (c) (e)
 $38.31
 $37.81
 $76.43
Realized residue natural gas net sales price ($/MMBtu) (c) (e)
 $2.80
 $3.64
 $3.92
Average fee rate ($MMBtu)
 $0.76
 $0.44
 $0.36
 $0.92
 $0.90
 $0.86
(a) - Includes volumes for consolidated entities only.
(b) - Includes volumes at company-owned and third-party facilities.
(c)
2019 vs. 2018 - Includes the impact of hedging activities on ONEOK Partners’ equity volumes.
(d) - Net of transportation and fractionation costs.
(e) - Net of transportation costs.

Natural gas gathered, andnatural gas processed, NGL sales and residue natural gas sales volumes increased in 2016,2019, compared with 2015,2018, due primarily to our capital-growth projects and continued producer improvements in production due to theenhanced completion of capital-growth projects in the Rocky Mountain region,techniques, offset partially by natural gas volume declines in the Mid-

Continent region due to natural production declines on existing wells, delays in completion of several multi-well pads and the impact of weather in the Williston Basin in December 2016. Natural gas gathered and processed, NGL sales and residue natural gas sales increased in 2015, compared with 2014, due to the completion of growth projects in the Rocky Mountain region, offset partially by unplanned outages in the Rocky Mountain region during the third quarter and natural gas volume declines in the Mid Continent region due to natural production declines.


The quantity and composition of NGLs and natural gas have varied as new plants were placed in service and to ensure natural gas and natural gas liquids pipeline specifications were met. Beginning in June 2015, ONEOK Partners reduced the level of ethane rejection in the Rocky Mountain region to address downstream NGL product specifications.

  Years Ended December 31,
Equity Volume Information (a) 2016 2015 2014
       
NGL sales (MBbl/d)
 14.6
 20.9
 16.5
Condensate sales (MBbl/d)
 2.4
 2.8
 3.1
Residue natural gas sales (BBtu/d)
 80.0
 136.2
 118.2
(a) - Includes volumes for consolidated entities only.

Equity volumes decreased in 2016 as a result of ONEOK Partners’ contract restructuring efforts. As contracts are renewed or restructured, ONEOK Partners has generally increased the fee component and lowered the percentage of proceeds that it retains from the sale of commodities.

Commodity Price Risk - See discussion regarding ONEOK Partners’our commodity price risk under “Commodity Price Risk” in Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

Impairment Charges - Due to the continued and greater than expected decline in volumes gathered in the dry natural gas area of the Powder River Basin, ONEOK Partners evaluated its long-lived assets and equity investments in this area in 2015 and made the decision to cease operations of its wholly owned coal-bed methane natural gas gathering system in 2016. This resulted in a $63.5 million noncash impairment charge to ONEOK Partners’ long-lived assets in 2015. Bighorn Gas Gathering, in which ONEOK Partners owns a 49 percent equity interest, and Fort Union Gas Gathering, in which ONEOK Partners owns a 37 percent equity interest, were both partially supplied with volumes from ONEOK Partners’ wholly owned coal-bed methane natural gas gathering system. ONEOK Partners also owns a 35 percent equity interest in Lost Creek Gathering Company, which also is located in a dry natural gas area. ONEOK Partners reviewed its Bighorn Gas Gathering, Fort Union Gas Gathering and Lost Creek Gathering Company equity investments and recorded noncash impairment charges of $180.6 million in 2015. The remaining net book value of ONEOK Partners’ equity investments in this dry natural gas area is $31.1 million as of December 31, 2016.

In 2015, ONEOK Partners also recorded a noncash impairment charge of $10.2 million related to a previously idled asset, as the expectation for future use of the asset changed.

In 2014, Bighorn Gas Gathering recorded an impairment of its underlying assets when the operator determined that the volume decline would be sustained for the foreseeable future. As a result, ONEOK Partners reviewed its equity investment in Bighorn Gas Gathering for impairment and recorded noncash impairment charges of $76.4 million in 2014 related to Bighorn Gas Gathering.


Natural Gas Liquids


Growth Projects - ONEOK Partners’ growth strategy in theOur Natural Gas Liquids segment invests in projects to transport, fractionate, store and deliver to market centers NGL supply from shale and other resource development areas. Our growth strategy is focused around the crude oil and NGL-rich natural gas drilling activity in shale and other nonconventional resource areasconnecting diversified supply basins from the Rocky Mountain region through the Mid-Continent region into Texas and New Mexico. Crude oil, natural gas andthe Permian Basin with NGL productionproduct demand from this activity; higher petrochemical industry demand for NGL products; and increased exports have resulted in additional capital investments to expand its infrastructure to bring these commodities from supply basins to market. Expansion of the petrochemical industry in the United States is expected to increase ethane demand beginning in the second half of 2017, and international demand for NGLs, particularly ethane and propane, also is increasing.

The Natural Gas Liquids segment invests in NGL-related projects to accommodate the transportation, fractionation and storage of NGL supply from shale and other resource development areas across ONEOK Partners’ asset base and alleviate expected

infrastructure constraints between the Mid-Continent and Gulf Coast market centers to meet increasing petrochemical industry and NGL export demand in the Gulf Coast. Growing crude oil, natural gas and NGL production together with higher petrochemical and export demand have resulted in us making additional capital investments to expand our infrastructure and alleviate system constraints. See “Growth Projects” in the “Recent Developments” section for discussion of our announced capital-growth projects.


We continue to evaluate opportunities to increase the capacity of our gathering, fractionation, storage and distribution assets or construct new assets to connect supply growth from the Williston and Powder River Basins, Mid-Continent region and Permian Basin with end-use markets.

In August 2016, ONEOK Partners completed the Bear Creek2019, we connected seven third-party natural gas processing plants and one affiliate natural gas processing plant to our NGL infrastructure projectsystem, five in the Williston Basin for approximately $45 million, excluding AFUDC. In April 2015, ONEOK Partners completed the NGL Pipeline and Hutchinson Fractionator infrastructure project for approximately $120 million, excluding capitalized interest.

Construction of Phase II of the Bakken NGL Pipeline expansion is planned for completionMid-Continent region, one in the third quarter 2018, which is expectedPermian Basin and two in the Rocky Mountain region. In addition, six third-party natural gas processing plants connected to increase capacity by 25 MBbl/dour system were expanded, two in the Mid-Continent region, two in the Permian Basin and cost approximately $100 million, excluding AFUDC.two in the Rocky Mountain region.


For a discussion of ONEOK Partners’our capital expenditure financing, see “Capital Expenditures” in the “Liquidity and Capital Resources” section.


Selected Financial Results and Operating Information-The following tables set forth certain selected financial results and operating information for theour Natural Gas Liquids segment for the periods indicated:
      Variances Variances
  Years Ended December 31, 2016 vs. 2015 2015 vs. 2014
Financial Results 2016 2015 2014 Increase (Decrease) Increase (Decrease)
  
(Millions of dollars)
NGL and condensate sales $6,152.5
 $5,200.8
 $9,462.4
 $951.7
 18 % $(4,261.6) (45)%
Exchange service revenues 1,327.5
 1,196.9
 910.2
 130.6
 11 % 286.7
 31 %
Transportation and storage revenues 195.7
 182.0
 172.8
 13.7
 8 % 9.2
 5 %
Cost of sales and fuel (exclusive of depreciation and items shown separately below) (6,321.4) (5,328.3) (9,435.3) 993.1
 19 % (4,107.0) (44)%
Operating costs (327.6) (314.5) (296.4) 13.1
 4 % 18.1
 6 %
Equity in net earnings from investments 54.5
 38.7
 27.3
 15.8
 41 % 11.4
 42 %
Other (1.6) (3.3) (0.1) 1.7
 52 % (3.2) *
Adjusted EBITDA $1,079.6
 $972.3
 $840.9
 $107.3
 11 % $131.4
 16 %
Capital expenditures $105.9
 $226.1
 $798.0
 $(120.2) (53)% $(571.9) (72)%
Cash paid for acquisitions, net of cash received $
 $
 $800.9
 $
  % $(800.9) (100)%
* Percentage change is greater than 100 percent.
        Variances
  Years Ended December 31, 2019 vs. 2018 2018 vs. 2017
Financial Results 2019 2018 2017 Increase (Decrease)
  
(Millions of dollars)
NGL and condensate sales $7,910.8
 $10,319.9
 $8,998.9
 $(2,409.1) $1,321.0
Exchange service revenues and other 424.2
 415.7
 1,430.3
 8.5
 (1,014.6)
Transportation and storage revenues 197.5
 199.0
 197.0
 (1.5) 2.0
Cost of sales and fuel (exclusive of depreciation and operating costs) (6,690.9) (9,176.8) (9,176.5) (2,485.9) 0.3
Operating costs, excluding noncash compensation adjustments (434.4) (378.3) (351.3) 56.1
 27.0
Equity in net earnings from investments 65.1
 67.1
 59.9
 (2.0) 7.2
Other (6.5) (6.0) (3.4) (0.5) (2.6)
Adjusted EBITDA $1,465.8
 $1,440.6
 $1,154.9
 $25.2
 $285.7
Capital expenditures $2,796.6
 $1,306.3
 $114.3
 $1,490.3
 $1,192.0
See reconciliation of net income to adjusted EBITDA in the “Adjusted EBITDA” section.


Due to the nature of ONEOK Partners’ contracts, changesChanges in commodity prices and sales volumes affect commodity salesboth revenues and cost of sales and fuel, and, therefore, the impact is largely offset between these line items.


20162019 vs. 20152018 - Adjusted EBITDA increased $107.3$25.2 million, primarily as a result of the following:
an increase of $90.0$148.1 million in exchange services due to increased exchange services$150.2 million in higher volumes from recently connected natural gas processing plants primarily in the WillistonRocky Mountain region, the Permian Basin increased Mid-Continent volumes gathered inand the STACK and SCOOP areas, and increased volumes resulting from increased ethane recovery$91.5 million in higher average fee rates primarily fromin the WillistonPermian Basin to maintain downstream NGL product specifications;and the Rocky Mountain region, offset partially by lower volumes and rates on the West Texas LPG system and the impact of weather on ONEOK Partners’ system in December 2016;
an increase of $15.8$64.9 million in equity in net earnings from investments due primarily to higher volumes delivered to Overland Pass Pipeline from the Bakken NGL Pipeline;
an increase of $13.8 million inthird-party transportation and storage services due to higher storage and terminaling revenue in the Gulf Coast and revenues from minimum volume obligations on ONEOK Partners’ distribution pipelines;
an increase of $8.4fractionation costs, $25.0 million related to higher isomerization volumes resulting from wider NGL price differentials between normal butane and iso-butane; and
an increase of $4.3 million due to the impact of operational measurement gains in 2016 and operational measurement losses in 2015; offset partially by
a decrease of $13.8 million in optimization and marketing activities, which resulted from a $20.0 million decrease due primarily to narrower product price differentials and $5.8 million related to higher unfractionated NGLs in inventory; offset partially by
a decrease of $60.2 million in optimization and marketing due primarily to a decrease of $93.8 million related to wider location price differentials in the prior year, particularly in the third quarter 2018, and $5.1 million in lower earnings related primarily to product price differentials, offset partially by a $6.2higher marketing earnings of $38.5 million increase duerelated primarily to higher optimization volumes;the sale of NGL products previously held in inventory; and
an increase of $13.1$56.1 million in operating costs due primarily to higher employee-related costs associated with incentivelabor and medical benefit plans.benefits due to the growth of our operations, and spending on routine maintenance projects.



Capital expenditures decreasedincreased due primarily to spending reductions for growth capital to align with customer needs.our announced capital-growth projects.

2015 vs. 2014 - Adjusted EBITDA increased $131.4 million, primarily as a result of the following:
an increase of $288.1 million in exchange services, which includes:
an increase of $191.0 million, which resulted from increased volumes from new plants connected in the Williston Basin and Mid-Continent region and higher revenues from customers with minimum volume obligations;
an increase of $75.0 million due primarily to the acquisition of the West Texas LPG system in the Permian Basin, which was acquired in November 2014; and
an increase of $23.8 million resulting from decreased ethane rejection in the Williston Basin resulting from downstream NGL product specification issues, offset partially by higher ethane rejection in the Mid-Continent region;
an increase of $11.4 million in equity in net earnings from investments due primarily to higher volumes delivered to Overland Pass Pipeline from the Bakken NGL Pipeline; and
an increase of $6.8 million in transportation revenues due primarily to increased volumes on ONEOK Partners’ distribution pipelines; offset partially by
a decrease of $118.4 million in optimization, marketing and differentials-based activities, which resulted from a $66.3 million decrease due primarily to narrower NGL product price differentials, a $27.7 million decrease due primarily to narrower NGL location price differentials and a $24.4 million decrease in the marketing business. A portion of this decrease relates to the increased demand for propane experienced during the first quarter 2014;
a decrease of $29.9 million related to lower isomerization volumes resulting from narrower NGL price differential between normal butane and iso-butane;
an increase of $18.1 million in operating costs primarily as a result of the completion of growth projects and West Texas LPG acquisition, which includes:
an increase of $29.2 million due to the West Texas LPG acquisition; and
an increase of $6.5 million due to higher ad valorem taxes; offset partially by
a decrease of $17.6 million due to reduced operating costs resulting from lower rates charged by service providers, primarily from $6.6 million lower outside services, $5.0 million lower supplies and expenses and $3.2 million lower chemicals and materials; and
a decrease of $6.9 million due to the impact of operational losses in 2015 and operational measurement gains in 2014.

Capital expenditures decreased due primarily to the completion of several growth projects in 2014 and spending reductions for growth capital to align with customer needs.

In 2015, ONEOK Partners recorded a noncash impairment charge of $10.0 million related to a previously idled asset, as the expectation for future use of the asset changed.


  Years Ended December 31,
Operating Information 2016 2015 2014
NGLs transported - gathering lines (MBbl/d) (a)
 770
 769
 533
NGLs fractionated (MBbl/d) (b)
 586
 552
 522
NGLs transported - distribution lines (MBbl/d) (a)
 508
 428
 408
Average Conway-to-Mont Belvieu OPIS price differential -
ethane in ethane/propane mix ($/gallon)
 $0.03
 $0.02
 $0.05
  Years Ended December 31,
Operating Information 2019 2018 2017
Raw feed throughput (MBbl/d) (a)
 1,079
 1,010
 895
NGLs transported - gathering lines (MBbl/d) (b) 988
 912
 812
NGLs fractionated (MBbl/d) (c) 726
 715
 621
Average Conway-to-Mont Belvieu OPIS price differential -
ethane in ethane/propane mix ($/gallon)
 $0.07
 $0.15
 $0.05
(a) - Represents physical raw feed volumes on which we charge a fee for transportation and/or fractionation services.
(b) - Includes volumes for consolidated entities only.
(b)(c) - Includes volumes at company-owned and third-party facilities.


20162019 vs. 20152018 - NGLs transported on gathering lines remained relatively unchanged due toRaw feed throughput volumes increased volumes from new plant connectionsprimarily in the WillistonRocky Mountain region, the Permian Basin increased ethane recovery and increased Mid-Continent volumes gathered in the STACK and SCOOP areas offset by decreased volumes on the West Texas LPG system, decreased Mid-Continent volumes gathered from the Barnett Shale, lower short-term contracted volumesas a result of our completed capital-growth projects, continued drilling and the impact of weather on gathered volumes across ONEOK Partners’ systemproducer improvements in December 2016.

NGLs fractionated increasedproduction due to increased volumes from new plant connections in the Williston Basin, increased ethane recovery and increased Mid-Continent volumes gathered in the STACK and SCOOP areas,enhanced completion techniques, offset partially by decreased

volumes gathered from the Barnett Shalenatural production declines and lower short-term contracted volumes andin the impact of weather on gathered volumes across ONEOK Partners’ system in December 2016.

While the volume of ethane recovered increased, a portion of the fees associated with those volumes gathered and fractionated was previously being earned under contracts with minimum volume obligations.

NGLs transported on distribution lines increasedMid-Continent region due primarily to higher gathered and fractionated volumes as discussed above and due to increased volumes transported for ONEOK Partners’ optimization business.lower ethane volumes.


2015 vs. 2014 - NGLs transported on gathering lines and NGLs fractionated increased due to increased volumes from new plant connections in the Williston Basin and Mid-Continent region and decreased ethane rejection in the Rocky Mountain region, offset partially by increased ethane rejection in the Mid-Continent region. The decreased ethane rejection in the Rocky Mountain region began in June 2015 due to downstream NGL product specifications and increased gathered volumes by approximately 20 MBbl/d in the second half of 2015. NGLs transported on gathering lines also increased significantly due to volumes from the Permian Basin transported on the West Texas LPG system, which was acquired in November 2014.

NGLs transported on distribution lines increased due primarily to higher gathered and fractionated volumes as discussed above and due to increased volumes transported for ONEOK Partners’ optimization business.

Natural Gas Pipelines


Growth Projects - Roadrunner is a 50 percent-owned joint venture equity-method investment project. The WesTex pipeline expansion is a wholly owned project.

ONEOK Partners completed the following growth projects in this segment in 2016:
Completed ProjectsLocationCapacity
Approximate
Costs (a)
Completion Date
(In millions)
WesTex Pipeline ExpansionPermian Basin260 MMcf/d$55October 2016
Roadrunner Gas Transmission Pipeline - Equity-Method Investment
Phase I (b)Permian Basin170 MMcf/d$200March 2016
Phase II (b)Permian Basin400 MMcf/d$210October 2016
Roadrunner Gas Transmission Pipeline Total$410
(a) - Excludes capitalized interest.
(b) - 50-50 joint venture equity-method investment. Approximate costs represents total project costs.

Roadrunner - Phase I and Phase II of the Roadrunner pipeline were completed in March and October 2016, respectively. Phase II of Roadrunner was completed ahead of original schedule and below cost estimates. Construction of Phase III of Roadrunner is planned for completion in 2019, which will increase capacity by 70 MMcf/d and cost approximately $30 million-$40 million.

ONEOK Partners contributed approximately $65 million and $30 million to Roadrunner in 2016 and 2015, respectively.

Both the WesTex pipeline expansion and Roadrunner are fully subscribed with 25-year firm demand charge, fee-based agreements. Together, these projects provide markets in Mexico access to upstream supply basins in West Texas and the Mid-Continent region.


Selected Financial Results and Operating Information -The following tables set forth certain selected financial results and operating information for the Natural Gas Pipelines segment for the periods indicated:
      Variances Variances
  Years Ended December 31, 2016 vs. 2015 2015 vs. 2014
Financial Results 2016 2015 2014 Increase (Decrease) Increase (Decrease)
  
(Millions of dollars)
Transportation revenues $288.5
 $258.6
 $270.5
 $29.9
 12 % $(11.9) (4)%
Storage revenues 60.0
 57.1
 64.0
 2.9
 5 % (6.9) (11)%
Natural gas sales and other revenues 30.9
 16.7
 15.9
 14.2
 85 % 0.8
 5 %
Cost of sales and fuel (exclusive of depreciation and items shown separately below) (30.6) (34.5) (21.9) (3.9) (11)% 12.6
 58 %
Operating costs (115.6) (105.7) (111.0) 9.9
 9 % (5.3) (5)%
Equity in net earnings from investments 74.4
 68.7
 69.8
 5.7
 8 % (1.1) (2)%
Other 5.5
 14.1
 6.9
 (8.6) (61)% 7.2
 *
Adjusted EBITDA $313.1
 $275.0
 $294.2
 $38.1
 14 % $(19.2) (7)%
Capital expenditures $96.3
 $58.2
 $43.0
 $38.1
 65 % $15.2
 35 %
Cash paid for acquisitions $
 $
 $14.0
 $
  % $(14.0) (100)%
* Percentage change is greater than 100 percent.
See reconciliation of net income to adjusted EBITDA in the “Adjusted EBITDA” section.

2016 vs. 2015 - Adjusted EBITDA increased $38.1 million primarily as a result of the following:
an increase of $28.5 million from higher transportation services due primarily to increased firm demand charge contracted capacity;
an increase of $9.3 million from higher net retained fuel due to higher throughput and the associated natural gas volumes retained and higher equity gas sales related to transportation and storage services;
an increase of $6.6 million due to higher natural gas storage services as a result of increased storage rates and increased sales of excess natural gas in storage; and
an increase of $5.7 million in equity earnings due primarily to higher firm transportation revenues on Northern Border Pipeline and Roadrunner; offset partially by
an increase of $9.9 million in operating costs due primarily to increased employee-related costs associated with incentive and medical benefit plans and higher ad valorem taxes.

Capital expenditures increased due primarily to the WesTex pipeline expansion and other expansion projects.

2015 vs. 2014 - Adjusted EBITDA decreased $19.2 million primarily as a result of the following:
a decrease of $16.6 million from lower short-term natural gas storage services as a result of weather-related seasonal demand associated with severely cold weather in the first quarter 2014 and lower sales of excess natural gas in storage;
a decrease of $10.0 million from lower net retained fuel due to lower natural gas prices and natural gas volumes retained; and
a decrease of $5.0 million from lower park-and-loan services on ONEOK Partners’ interstate pipelines as a result of weather-related seasonal demand due to severely cold weather in the first quarter 2014; offset partially by
an increase of $8.6 million due to higher transportation revenues, primarily from increased rates on intrastate pipelines and higher rates on Viking Gas Transmission as a result of the FERC approved settlement, effective January 2015, offset partially by decreased interruptible transportation revenues from lower natural gas volumes transported; and
a decrease of $5.3 million in operating costs primarily as a result of lower materials and supplies and outside services expenses.

Capital expenditures increased due primarily to a compressor station expansion project.


  Years Ended December 31,
Operating Information (a) 2016 2015 2014
Natural gas transportation capacity contracted (MDth/d)
 6,345
 5,840
 5,781
Transportation capacity subscribed 92% 92% 91%
Average natural gas price  
  
  
Mid-Continent region ($/MMBtu)
 $2.28
 $2.42
 $4.33
(a) - Includes volumes for consolidated entities only.

ONEOK Partners’Our natural gas pipelines primarily serve end users, such as natural gas distribution and electric-generation companies, that require natural gas to operate their businesses regardless of location price differentials. The development of shale and other resource areas has continued to increase available natural gas supply, resulting in narrower location and seasonal price differentials. As additional supply is developed, we expect crude oilproducers and natural gas producersprocessors to demandrequire incremental transportation services in the future to transport their production to market. The abundance ofas additional supply is developed.

We expanded our natural gas supplypipeline infrastructure in Oklahoma and regulationsthe Permian Basin. The projects included an eastbound expansion of our ONEOK Gas Transportation system by 150 MMcf/d from the STACK and SCOOP areas to an interstate pipeline delivery point in eastern Oklahoma, a westbound expansion of our ONEOK Gas Transportation system by
100 MMcf/d from the STACK area to multiple interstate pipeline delivery points in western Oklahoma and an expansion of our WesTex Transmission system by 300 MMcf/d from the Permian Basin to interstate pipeline delivery points in the Texas Panhandle. Additionally, we completed an expansion project on emissionsour Roadrunner joint venture to make the pipeline bidirectional, which resulted in approximately 1.0 Bcf/d of eastbound transportation capacity from coal-fired electric-generation plants may also increase the demandDelaware Basin to the Waha area.

See “Capital Expenditures” in “Liquidity and Capital Resources” for ONEOK Partners’ services from electric-generation companies if they convertadditional detail of our projected capital expenditures.

Selected Financial Results and Operating Information -The following tables set forth certain selected financial results and operating information for our Natural Gas Pipelines segment for the periods indicated:
        Variances
  Years Ended December 31, 2019 vs. 2018 2018 vs. 2017
Financial Results 2019 2018 2017 Increase (Decrease)
  
(Millions of dollars)
Transportation revenues $393.7
 $343.0
 $327.9
 $50.7
 $15.1
Storage revenues 72.6
 72.0
 66.5
 0.6
 5.5
Natural gas sales and other revenues 5.7
 16.7
 25.5
 (11.0) (8.8)
Cost of sales and fuel (exclusive of depreciation and operating costs) (4.6) (16.0) (43.4) (11.4) (27.4)
Operating costs, excluding noncash compensation adjustments (150.8) (139.2) (123.1) 11.6
 16.1
Equity in net earnings from investments 95.7
 90.8
 87.3
 4.9
 3.5
Other (3.5) (1.0) (0.9) (2.5) (0.1)
Adjusted EBITDA $408.8
 $366.3
 $339.8
 $42.5
 $26.5
Capital expenditures $99.2
 $119.2
 $95.6
 $(20.0) $23.6
See reconciliation of net income to adjusted EBITDA in the “Adjusted EBITDA” section.

2019 vs. 2018 - Adjusted EBITDA increased $42.5 million primarily as a natural gas fuel source. Overall, we expect ONEOK Partners’ fee-based earnings in this segment to increase in connection with the October 2016 completionresult of the following:
an increase of $56.5 million from higher transportation services due primarily to firm transportation capacity contracted due to our completed expansion projects; and
an increase of $4.9 million from higher equity in net earnings due primarily to firm transportation capacity contracted on Roadrunner; offset partially by
an increase of $11.6 million in operating costs due primarily to employee-related costs associated with labor and benefits and ad valorem taxes due to the growth of our operations; and
a decrease of $9.1 million from lower net retained fuel and timing of equity gas sales.

Capital expenditures decreased due primarily to timing of maintenance projects and capital-growth projects.

  Years Ended December 31,
Operating Information (a) 2019 2018 2017
Natural gas transportation capacity contracted (MDth/d)
 7,618
 6,846
 6,611
Transportation capacity contracted 98% 96% 94%
(a) - Includes volumes for consolidated entities only.

2019 vs. 2018 - Natural gas transportation capacity contracted increased due to our completed expansion projects on our ONEOK Gas Transportation and WesTex pipeline expansion.Transmission systems, which are both substantially contracted.

Roadrunner, in which we have a 50% ownership interest, has contracted all of its westbound capacity through 2041.

Northern Border Pipeline, in which ONEOK Partners haswe have a 50 percent50% ownership interest, has contracted substantially all of its long-haul transportation capacity through the firstfourth quarter 2018.2020.


Roadrunner,In June 2019, our subsidiary, Viking Gas Transmission Company, filed a proposed change in which ONEOK Partners hasrates pursuant to Section 4 of the Natural Gas Act with the FERC. In February 2020, all parties agreed to a 50 percent ownership interest, has contracted allsettlement in principle and plan to present it to FERC for approval. We do not expect the ultimate outcome to impact materially our results of its capacity through 2041.operations.


Adjusted EBITDA


Adjusted EBITDA is a non-GAAP measure of the Partnership’sour financial performance. Adjusted EBITDA is defined as net income adjusted for interest expense, depreciation and amortization, noncash impairment charges, income taxes, allowance for equity funds used during construction, noncash compensation and other noncash items. We believe this non-GAAP financial measure is useful to investors because it and similar measures are used by many companies in our industry as a measurement of financial performance and areis commonly employed by financial analysts and others to evaluate our financial performance and to compare financial performance among companies in our industry. Adjusted EBITDA should not be considered an alternative to net income, earnings per unitshare or any other measure of financial performance presented in accordance with GAAP. Additionally, this calculation may not be comparable with similarly titled measures of other companies.


AThe following table sets forth a reconciliation of net income, the nearest comparable GAAP financial performance measure, to adjusted EBITDA for the yearsperiods indicated:
  Years Ended December 31,
(Unaudited)
 2019 2018 2017
Reconciliation of net income to adjusted EBITDA 
(Thousands of dollars)
Net income $1,278,577
 $1,155,032
 $593,519
Add:      
Interest expense, net of capitalized interest 491,773
 469,620
 485,658
Depreciation and amortization 476,535
 428,557
 406,335
Income taxes 372,414
 362,903
 447,282
Impairment charges 
 
 20,240
Noncash compensation expense 26,699
 37,954
 13,421
Equity AFUDC and other noncash items (a) (65,811) (6,545) 20,398
Adjusted EBITDA $2,580,187
 $2,447,521
 $1,986,853
Reconciliation of segment adjusted EBITDA to adjusted EBITDA      
Segment adjusted EBITDA:      
Natural Gas Gathering and Processing $702,650
 $631,607
 $518,472
Natural Gas Liquids 1,465,765
 1,440,605
 1,154,939
Natural Gas Pipelines 408,816
 366,251
 339,818
Other (b) 2,956
 9,058
 (26,376)
Adjusted EBITDA $2,580,187
 $2,447,521
 $1,986,853
(a) - Year ended December 31, 2016, 2015 and 2014, is as follows:2017, includes our April 2017 contribution to the Foundation of 20,000 shares of Series E Preferred Stock, with an aggregate value of $20.0 million.
(b) - Year ended December 31, 2017, includes Merger Transaction costs of $30.0 million.
  Years Ended December 31,
(Unaudited)
 2016 2015 2014
Reconciliation of net income to adjusted EBITDA 
(Thousands of dollars)
Net income from continuing operations $745,550
 $385,276
 $668,715
Add:      
Interest expense, net of capitalized interest 469,651
 416,787
 356,163
Depreciation and amortization 391,585
 354,620
 294,684
Income taxes 212,406
 136,600
 151,158
Impairment charges 
 264,256
 76,412
Allowance for equity funds used during construction and other 9,482
 2,762
 (20,366)
Adjusted EBITDA $1,828,674
 $1,560,301
 $1,526,766
Reconciliation of segment adjusted EBITDA to adjusted EBITDA      
Segment adjusted EBITDA:      
Natural Gas Gathering and Processing $446,778
 $318,554
 $425,170
Natural Gas Liquids 1,079,619
 972,292
 840,922
Natural Gas Pipelines 313,137
 274,980
 294,202
Total segment adjusted EBITDA 1,839,534
 1,565,826
 1,560,294
Other corporate costs (10,860) (5,525) (33,528)
Adjusted EBITDA $1,828,674
 $1,560,301
 $1,526,766


CONTINGENCIES

Legal Proceedings - See Part I, Item 3, Legal Proceedings, in this Annual Report for a discussion of developments concerning the Gas Pricing Index Litigation and other legal proceedings.


LIQUIDITY AND CAPITAL RESOURCESCONTINGENCIES


General - We fund operating expenses, debt service and dividends to shareholders primarily from cash on hand and cash distributions received from ONEOK Partners.

Neither ONEOK nor ONEOK Partners guarantees the debt or other similar commitments of unaffiliated parties. ONEOK does not guarantee the debt or other similar commitments of ONEOK Partners, and ONEOK Partners does not guarantee the debt or other similar commitments of ONEOK. Following the completion of the Merger Transaction with ONEOK Partners described inSee Note BN of the Notes to Consolidated Financial Statements in this Annual Report we and ONEOK Partners expect to enter intofor a cross guarantee agreement whereby eachdiscussion of regulatory matters.

Other Legal Proceedings -We are a party to various litigation matters and claims that have arisen in the agreement unconditionally guaranteesnormal course of our operations. While the results of these litigation matters and becomes liable forclaims cannot be predicted with certainty, we believe the indebtednessreasonably possible losses from such matters, individually and in the aggregate, are not material. Additionally, we believe the probable final outcome of each other party to the agreement.such matters will not affect adversely our consolidated results of operations, financial position or cash flows.


ONEOKLIQUIDITY AND CAPITAL RESOURCES

General - ONEOK’s primary source of cash inflows are distributions to us from our general partner and limited partner interests in ONEOK Partners. The cash distributions that we expect to receive from ONEOK Partners are expected to provide sufficient resources to fund our operations, debt service and quarterly cash dividends. In addition, we incur certain costs on behalf of ONEOK Partners for which we are reimbursed. At December 31, 2016, we had approximately $249 million of cash on hand. Our next long-term debt maturity is in 2022.

Following the completion of the Merger Transaction with ONEOK Partners, the cash flow sources and requirements for ONEOK are expected to change significantly, as we will receive cash flows directly from operations and fund all capital expenditures. Additionally, we expect to have access to a significantly larger credit facility. Our primary sources of cash inflows are expected to be from operating cash flows, proceeds from our commercial paper bank credit facilities,program and our $2.5 Billion Credit Agreement, debt issuances and the issuance of common stock.stock for our liquidity and capital resources requirements. In addition, we expect cash outflows related to i) capital expenditures, ii) interest and repayment of debt maturities and iii) dividends paid to shareholders. We expect theseour cash outflows related to capital expenditures to decrease in 2020 relative to 2019 due to our completed capital-growth projects. We expect dividends paid to continue to increase due to earnings growth from capital projects and higher anticipated dividends per share, subject to declaration by our Board of Directors.

We expect our sources of cash flowinflows to provide sufficient resources to finance our operations, capital expenditures and quarterly cash dividends. ONEOKdividends, including expected future dividend increases. Our $2.5 Billion Credit Agreement, which expires in June 2024, provides significant liquidity to fund capital expenditures and repay existing indebtedness. We may access the capital markets to issue debt or equity securities in 2017 as it considerswe consider prudent to provide additional liquidity to refinance existing debt, improve credit metrics or for other corporate purposes.

ONEOK Partners - ONEOK Partners relies primarily on operating cash flows, commercial paper, bank credit facilities, debt issuances and the issuance of common units for its liquidity andto fund capital resources requirements. ONEOK Partners funds its operating expenses, debt service and cash distributionsexpenditures. Although we expect to its limited partners and general partnercontinue to fund capital projects primarily with operating cash flows. To the extent operating cash flows are not sufficient to fund its cash distributions, ONEOK Partners may utilize short-from operations, short-term borrowings and long-term debt, we continue to have access to $550 million available through our “at-the-market” equity program and issuances of equity, as necessary. Capital expenditures are funded by operating cash flows, short- and long-term debt and issuances of equity. ONEOK Partners’the ability to continue to access capital markets for debtissue equity and equity financingother securities under reasonable terms depends on its financial condition, credit ratings and market conditions. While lower commodity prices and industry uncertainty may result in increased financing costs, we believe ONEOK Partners has secured sufficient access to the financial resources and liquidity necessary to meet its requirements for working capital, debt service payments and capital expenditures. our universal shelf registration statement.

We believe that its available credit and cash and cash equivalents are adequate to meet liquidity requirements associated with commodity price volatility. ONEOK Partners may access the capital markets to issue debt or equity securities in 2017 as it considers prudent to provide liquidity for new capital projects, to refinance existing debt, to maintain investment-grade credit ratings or for other partnership purposes.

ONEOK Partners managesmanage interest-rate risk through the use of fixed-rate debt, floating-rate debt and interest-rate swaps. For additional information on ONEOK Partners’ interest rateour interest-rate swaps, see Note DC of the Notes to Consolidated Financial Statements in this Annual Report.


Cash Management-We and ONEOK Partners each use similara centralized cash management programsprogram that concentrateconcentrates the cash assets of our operating subsidiaries in joint accounts for the purposes of providing financial flexibility and lowering the cost of borrowing, transaction costs and bank fees. BothOur centralized cash management programs provideprogram provides that funds in excess of the daily needs of theour operating subsidiaries are concentrated, consolidated or otherwise made available for use by other entities within the respectiveour consolidated groups. ONEOK Partners’group. Our operating subsidiaries participate in this program to the extent they are permitted pursuant to FERC regulations or their operating agreements. Under thesethe cash management programs,program, depending on whether a participating subsidiary has short-term cash surpluses or cash requirements, we and ONEOK Partners provide cash to our respective subsidiariesthe subsidiary or the subsidiaries providesubsidiary provides cash to us and ONEOK Partners, respectively.us.



Short-term Liquidity-ONEOK’s sources of short-term liquidity are quarterly distributions from ONEOK Partners, cash on hand of approximately $249 million as of December 31, 2016, and access to our $300 million ONEOK Credit Agreement. At December 31, 2016, ONEOK had no short-term debt outstanding.

ONEOK Partners’ Our principal sources of short-term liquidity consist of cash generated from operating activities, distributions received from itsour equity-method investments, and proceeds from itsour commercial paper program and the ONEOK Partnersour $2.5 Billion Credit Agreement. As of December 31, 2019, we were in compliance with all covenants of the $2.5 Billion Credit Agreement.


ONEOK PartnersAt December 31, 2019, we had no borrowings outstanding under our $2.5 Billion Credit Agreement, $220 million of commercial paper outstanding and $21.0 million of cash and cash equivalents.

We had working capital (defined as current assets less current liabilities) deficits of $1.7 billion$550.0 million and $697$709.8 million as of December 31, 20162019, and 2015,December 31, 2018, respectively. Although working capital is influenced by several factors, including, among other things,things: (i) the timing of (a) debt and equity issuances, (b) the funding of capital expenditures, (c) scheduled debt payments, (b)and (d) the collection and payment of accounts receivable and payable, and (c) equity and debt issuances,payable; and (ii) the volume and cost of inventory and commodity imbalances, ONEOK Partners’imbalances; our working capital deficit at December 31, 2016,2019, was driven primarily by itsshort-term borrowings and accrued interest and at December 31, 2018, by current maturities of long-term debt and short-term borrowings. ONEOK Partners’ working capital deficit at December 31, 2015, was driven primarily by its capital-growth projects. ONEOK Partnersdebt. We may have working capital deficits in future periods as it continueswe continue to finance itsour capital-growth projects and repay long-term debt, often initially with short-term borrowings. ONEOK Partners’Our decision to utilize short-term borrowings rather than long-term debt was due to more favorable interest rates, contributes to its working capital deficit.rates. We do not expect ONEOK Partners’this working capital deficit to have an adverse impact toaffect adversely our or ONEOK Partners’ cash flows or operations. The consolidated working capital balance is impacted primarily by ONEOK Partners’ working capital balance.

ONEOK Credit Agreement - In January 2016, we extended the term of our ONEOK Credit Agreement by one year to January 2020. The ONEOK Credit Agreement is a $300 million revolving credit facility and contains certain financial, operational and legal covenants. At December 31, 2016, we had $1.1 million in letters of credit issued and $298.9 million of borrowing capacity under the ONEOK Credit Agreement.

ONEOK Partners Credit Agreement - At December 31, 2016, ONEOK Partners had $1.1 billion of commercial paper outstanding, $14 million of letters of credit issued and approximately $1.3 billion of borrowing capacity under the ONEOK Partners Credit Agreement.

In January 2016, ONEOK Partners extended the term of the ONEOK Partners Credit Agreement by one year to January 2020. The ONEOK Partners Credit Agreement is a $2.4 billion revolving credit facility and includes a $100 million sublimit for the issuance of standby letters of credit and a $150 million swingline sublimit. The ONEOK Partners Credit Agreement is available for general partnership purposes, and based on ONEOK Partners’ current credit ratings, borrowings, if any, will accrue interest at LIBOR plus 117.5 basis points. Amounts outstanding under ONEOK Partners’ commercial paper program reduce the borrowing capacity under the ONEOK Partners Credit Agreement. The ONEOK Partners Credit Agreement is guaranteed fully and unconditionally by the Intermediate Partnership.


For additional information on the ONEOKour $2.5 Billion Credit Agreement and ONEOK Partners Credit Agreement,commercial paper program, see Note GF of the Notes to Consolidated Financial Statements in this Annual Report.


Borrowings under the ONEOK Partners Credit Agreement, the Term Loan Agreement and ONEOK Partners’ senior notes are nonrecourse to ONEOK, and ONEOK does not guarantee ONEOK Partners’ debt, commercial paper or other similar commitments. Following the completion of the Merger Transaction with ONEOK Partners, we and ONEOK Partners expect to enter into a cross guarantee agreement whereby each party to the agreement unconditionally guarantees and becomes liable for the indebtedness of each other party to the agreement.

For information on ONEOK Partners’ distributions from and contributions to equity-method investments, see Note N of the Notes to Consolidated Financial Statements in this Annual Report.

Long-term Financing- In addition to our principal sources of short-term liquidity discussed above, we expect ONEOK Partners to fund itsour longer-term financing requirements by issuing common units or long-term notes. Other options to obtain financing include, but are not limited to, issuing common stock, loans from financial institutions, issuance of convertible debt securities or preferred equity securities, asset securitization and the sale and lease-back of facilities.


ONEOK Partners’ ability to obtain financing is subject to changes in the debt and equity markets, and there is no assurance it will be able or willing to access the public or private markets in the future. ONEOK Partners may choose to meet its cash requirements by utilizing some combination of cash flows from operations, borrowing under its commercial paper program or the ONEOK Partners Credit Agreement, altering the timing of controllable expenditures, restricting future acquisitions and capital projects, selling assets or pursuing other debt or equity financing alternatives. Some of these alternatives could result in

higher costs or negatively affect ONEOK Partners’ credit ratings, among other factors. Based on ONEOK Partners’ investment-grade credit ratings, general financial condition, and expectations regarding its future earnings and projected cash flows, we expect ONEOK Partners will be able to meet its cash requirements and maintain investment-grade credit ratings.

ONEOK debt issuanceDebt Issuances - In August 2015,2019, we completed an underwritten public offering of $2.0 billion senior unsecured notes consisting of $500 million, 7.5 percent2.75% senior notes due 2023. 2024; $750 million, 3.4% senior notes due 2029; and $750 million, 4.45% senior notes due 2049. The net proceeds, after deducting underwriting discounts, commissions and otheroffering expenses, were approximately $487.1 million. We used the proceeds together with cash on hand to purchase $650 million of additional common units from ONEOK Partners.

ONEOK debt$1.97 billion. The proceeds were used for general corporate purposes, including repayment - of existing indebtedness and funding capital expenditures.

In February 2014,March 2019, we retired approximately $152.5completed an underwritten public offering of $1.25 billion senior unsecured notes consisting of $700 million, excluding accrued and unpaid interest, of our 4.25 percent4.35% senior notes due 2022 through a tender offer. The total amount paid, including fees2029 and other charges, was approximately $150.0 million.

In March 2014, we repaidan additional issuance of $550 million of our $400 million, 5.2 percentexisting 5.2% senior notes due in 20152048. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, and exclusive of accrued interest, were $1.23 billion. The proceeds were used for $430.1 million,general corporate purposes, including accrued but unpaid interest to the redemption date.repayment of existing indebtedness and funding capital expenditures.


ONEOK Partners’ debt issuances and maturities - In January 2016, ONEOK PartnersNovember 2018, we entered into the $1.0 billion senior unsecured delayed-drawour $1.5 Billion Term Loan Agreement with a syndicate of banks. During the first quarter 2016, ONEOK Partners drew the full $1.0 billion available under the agreement and used the proceeds to repay $650banks, which was fully drawn as of June 30, 2019. We repaid $250 million of senior notes, which maturedour outstanding balance in February 2016, to repay amounts outstanding under its commercial paper programAugust 2019 and for general partnership purposes. Thehave $1.25 billion drawn as of December 31, 2019. Our $1.5 Billion Term Loan Agreement matures in January 2019November 2021 and bears interest at LIBOR plus 130112.5 basis points based on ONEOK Partners’our current credit ratings. The Term Loan Agreement contains an option, which may be exercised up to two times, to extend the term of the loan, in each case, for an additional one-year term subject to approval of the banks. The Term Loan Agreement allows prepayment of all or any portion outstanding, without penalty or premium, andagreement contains substantially the same covenants as those contained in the ONEOK Partnersour $2.5 Billion Credit Agreement. The proceeds were used for general corporate purposes, including repayment of existing indebtedness and funding capital expenditures.


ONEOK PartnersDebt Repayments - In September 2019, we redeemed our $300 million, 3.8% senior notes due March 2020 at a redemption price of $308.0 million, including the outstanding principal, plus accrued and unpaid interest, with cash on hand from our public offering of $2.0 billion senior unsecured notes in August 2019.

In August 2019, we repaid its $450$250 million 6.15 percentof our $1.5 Billion Term Loan agreement with cash on hand.

In March 2019, we repaid our $500 million, 8.625% senior notes at maturity in October 2016 with a combination of cash on hand and short-term borrowings.

In March 2015, ONEOK Partners completed an underwritten public offering of $800 million of senior notes, consisting of $300 million, 3.8 percent senior notes due 2020, and $500 million, 4.9 percent senior notes due 2025. The net proceeds were approximately $792.3 million. ONEOK Partners used the proceeds to repay amounts outstanding under its commercial paper program and for general partnership purposes.


For additional information on ONEOK and ONEOK Partners’our long-term debt, see Note GF of the Notes to Consolidated Financial Statements in this Annual Report.


ONEOK Partners’ equity issuancesCapital Expenditures- ONEOK Partners has an “at-the-market” equity program for the offer and sale from timeWe classify expenditures that are expected to time of its common units, up to an aggregate amount of $650 million. The program allows ONEOK Partners to offer and sell its common units at prices it deems appropriate through a sales agent. Sales of common unitsgenerate additional revenue, return on investment or significant operating efficiencies as capital-growth expenditures. Maintenance capital expenditures are made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between ONEOK Partners and the sales agent. ONEOK Partners is under no obligation to offer and sell common units under the program. At December 31, 2016, ONEOK Partners had approximately $138 million of registered common units available for issuance through its “at-the-market” equity program.

During the year ended December 31, 2016, no common units were sold through ONEOK Partners’ “at-the-market” equity program.

In August 2015, ONEOK Partners completed a private placement of 21.5 million common units at a price of $30.17 per unit with us. Additionally, ONEOK Partners completed a concurrent sale of approximately 3.3 million common units at a price of $30.17 per unit to funds managed by Kayne Anderson Capital Advisors in a registered direct offering, which were issued through its existing “at-the-market” equity program. The combined offerings generated net cash proceeds of approximately $749 million to ONEOK Partners. In conjunction with these issuances, ONEOK Partners GP contributed approximately $15.3 million in orderthose capital expenditures required to maintain our 2 percent general partner interest in ONEOK Partners. ONEOK Partners used the proceeds for general partnership purposes, including capital expendituresexisting assets and repayment of commercial paper borrowings.

During the year ended December 31, 2015, ONEOK Partners sold 10.5 million common units through its “at-the-market” equity program, including the units sold to funds managed by Kayne Anderson Capital Advisors in the offering discussed above. The net proceeds, including ONEOK Partners GP’s contribution to maintain our 2 percent general partner interest in

ONEOK Partners, were approximately $381.6 million to ONEOK Partners, which were used for general partnership purposes, including repayment of commercial paper borrowings.

In May 2014, ONEOK Partners completed an underwritten public offering of 13.9 million common units at a public offering price of $52.94 per common unit, generating net proceeds of approximately $714.5 million. In conjunction with this issuance, ONEOK Partners GP contributed approximately $15.0 million in order to maintain its 2 percent general partner interest in ONEOK Partners. ONEOK Partners used the proceeds for general partnership purposes, including capital expendituresoperations and repayment of commercial paper borrowings.

During the year ended December 31, 2014, ONEOK Partners sold 7.9 million common units through its “at-the-market” equity program. The net proceeds, including ONEOK Partners GP’s contribution to maintain our 2 percent general partner interest in ONEOK Partners, were approximately $402.1 million to ONEOK Partners, which were used for general partnership purposes.

Capital Expenditures -ONEOK’sdo not generate additional revenues. Maintenance capital expenditures are financed throughmade to replace partially or fully depreciated assets, to maintain the existing operating cash flows. ONEOK Partners’capacity of our assets and to extend their useful lives. Our capital expenditures are financed typically through operating cash flows and short- and long-term debt and the issuance of equity.debt.


The following table sets forth our growth and ONEOK Partners’maintenance capital expenditures, excluding AFUDC and capitalized interest, for the periods indicated:
Capital Expenditures 2016 2015 2014 2019 2018 2017
 
(Millions of dollars)
 
(Millions of dollars)
ONEOK $2.9
 $2.2
 $33.2
ONEOK Partners:      
Natural Gas Gathering and Processing 410.5
 887.9
 898.9
 $926.5
 $694.6
 $284.2
Natural Gas Liquids 105.9
 226.1
 798.0
 2,796.6
 1,306.3
 114.3
Natural Gas Pipelines 96.3
 58.2
 43.0
 99.2
 119.2
 95.6
Other 9.0
 13.9
 6.1
 26.0
 21.4
 18.3
Total capital expenditures $624.6
 $1,188.3
 $1,779.2
 $3,848.3
 $2,141.5
 $512.4


Capital expenditures decreasedincreased in 2016 and 2015,2019, compared with 2018, due primarily to ONEOK Partners’ completioncapital-growth projects in progress. We expect our 2020 capital expenditures to decrease relative to 2019 due to our completed capital-growth projects. See discussion of several largeour announced capital-growth projects and reduced capital spending to align within the needs of its crude oil and natural gas producers.“Recent Developments” section.


The following table sets forth ONEOK Partners’ 2017summarizes our 2020 projected growth and maintenance capital expenditures, excluding AFUDC and capitalized interest:
20172020 Projected Capital Expenditures
 
(Millions of dollars)
Natural Gas Gathering and ProcessingGrowth$215-2,250-$2602,730
Natural Gas LiquidsMaintenance$215-200-$260
Natural Gas Pipelines$80-$105
Other$10-$15220
Total projected capital expenditures$520-2,450-$6402,950

Credit Ratings-ONEOK and ONEOK Partners’ Our long-term debt credit ratings as of February 21, 2017,18, 2020, are shown in the table below:
ONEOKONEOK Partners
Rating AgencyLong-Term RatingShort-Term RatingRatingOutlook
Moody’sBa1Baa3Prime-3Baa2Positive
S&PBB+BBBA-2BBBStable


ONEOK Partners’ commercial paper program is rated Prime-2 by Moody’s and A-2 by S&P. In October 2016, Moody’s affirmed ONEOK Partners’ current credit ratings and revised its outlook to stable from negative. In December 2016, S&P affirmed ONEOK Partners’ and our current credit ratings and revised the outlooks to stable from negative. In February 2017, in conjunction with the announcement of the Merger Transaction with ONEOK Partners, S&P affirmed ONEOK Partners’ credit ratings and outlook and placed our credit ratings under review for upgrade, while Moody’s placed ONEOK Partners’ credit ratings under review for downgrade and placed our credit ratings under review for upgrade.


ONEOK Partners’Our credit ratings, which are investment grade, may be affected by a material change in itsour financial ratios or a material event affecting itsour business and industry. The most common criteria for assessment of ONEOK Partners’our credit ratings are the debt-to-EBITDA ratio, interest coverage, business risk profile and liquidity. If ONEOK Partners’our credit ratings were downgraded, theour cost to borrow funds under itsour $2.5 Billion Credit Agreement and our $1.5 Billion Term Loan Agreement the ONEOK Partners Credit Agreement and its commercial paper program would increase and ONEOK Partners could potentially losea potential loss of access to the commercial paper market.market could occur. In the event that ONEOK Partners iswe are unable to borrow funds under itsour commercial paper program and there has not been a material adverse change in itsour business, ONEOK Partnerswe would continue to have access to the ONEOK Partnersour $2.5 Billion Credit Agreement, which expires in January 2020.2024. An adverse credit rating change alone is not a default under the ONEOKour $2.5 Billion Credit Agreement or the ONEOK Partners Creditour $1.5 Billion Term Loan Agreement. A downgrade in ONEOK Partners’ credit ratings would likely result in a downgrade to ONEOK’s credit ratings. However, we wouldWe do not expect a downgrade toin our credit ratingsrating to have a material impact on our results of operations.


In the normal course of business, ONEOK Partners’our counterparties provide us with secured and unsecured credit. In the event of a downgrade in ONEOK Partners’our credit ratings or a significant change in ONEOK Partners’our counterparties’ evaluation of itsour creditworthiness, ONEOK Partnerswe could be required to provide additional collateral in the form of cash, letters of credit or other negotiable instruments as a condition of continuing to conduct business with such counterparties. ONEOK PartnersWe may be required to fund margin requirements with itsour counterparties with cash, letters of credit or other negotiable instruments.


ONEOK Partners Cash DistributionsDividends - ONEOK Partners distributes 100 percentHolders of its available cash, as definedour common stock share equally in its Partnership Agreement that generally consistsany common stock dividends declared by our Board of all cash receipts less adjustments for cash disbursements and net change to reserves, to its general and limited partners. Distributions are allocatedDirectors, subject to the general partnerrights of the holders of outstanding preferred stock. In 2019, we paid dividends of $3.53 per share, an increase of 9% compared with the prior year. In February 2020, we paid a quarterly dividend of $0.935 per share ($3.74 per share on an annualized basis), an increase of 9% compared with the same quarter in the prior year.

Our Series E Preferred Stock pays quarterly dividends on each share of Series E Preferred Stock, when, as and limited partners according to their partnership percentagesif declared by our Board of 2 percent and 98 percent, respectively. The effectDirectors, at a rate of any incremental allocations5.5% per year. In 2019, we paid dividends of $1.1 million for incentive distributions to the general partner is calculated afterSeries E Preferred Stock. In February 2020, we paid quarterly dividends totaling $0.3 million for the allocation to the general partner’s partnership interest and before the allocation to the limited partners.Series E Preferred Stock.


For the yearyears ended December 31, 2016, ONEOK Partners’2019 and 2018, cash flowflows from operations exceeded its cash distributions,dividends paid by $489.2 million and we$851.7 million, respectively. We expect ONEOK Partners’our cash flowflows from operations to exceed itscontinue to sufficiently fund our cash distributions in 2017. Fordividends. To the year ended December 31, 2015, ONEOK Partners’extent operating cash distributions exceeded its cash flow from operations and, as a result, ONEOK Partners utilized cash from operations, its commercial paper program and distributions received from its equity-method investmentsflows are not sufficient to fund cash distributions, short-term liquidity needsour dividends, we may utilize short- and capital projects.long-term debt and issuances of equity, as necessary or appropriate.

For additional information on ONEOK Partners’ cash distributions, see Note O of the Notes to Consolidated Financial Statements in this Annual Report.

Pension and Postretirement Benefit Plans - Information about our pension and postretirement benefits plans, including anticipated contributions, is included under Note L of the Notes to Consolidated Financial Statements in this Annual Report.

During 2016, we made no contributions to our defined benefit pension plans, and $1.0 million in contributions to our postretirement benefit plans. We contributed $7.5 million to our defined benefit pension plan in January 2017 and we expect to make approximately $2.0 million in contributions to our postretirement benefit plans in 2017.


CASH FLOW ANALYSIS


We use the indirect method to prepare our Consolidated Statements of Cash Flows. Under this method, we reconcile net income to cash flows provided by operating activities by adjusting net income for those items that affect net income but do not result in actual cash receipts or payments during the period and for operating cash items that do not impact net income. These reconciling items include depreciation and amortization, impairment charges, allowance for equity funds used during construction, gain or loss on sale of assets, deferred income taxes, equity in net undistributed earnings from equity-method investments, distributions received from unconsolidated affiliates, share-based compensation expense, other amounts and changes in our assets and liabilities not classified as investing or financing activities.



The following table sets forth the changes in cash flows by operating, investing and financing activities for the periods indicated:
 Years Ended December 31, Years Ended December 31,
 2016 2015 2014 2019 2018 2017
 
(Millions of dollars)
 
(Millions of dollars)
Total cash provided by (used in):            
Operating activities $1,351.6
 $1,007.0
 $1,285.6
 $1,946.8
 $2,186.7
 $1,315.4
Investing activities (615.4) (1,190.7) (2,566.2) (3,768.8) (2,114.9) (567.6)
Financing activities (584.8) 108.5
 1,304.5
 1,831.0
 (97.0) (959.5)
Change in cash and cash equivalents 151.4
 (75.2) 23.9
 9.0
 (25.2) (211.7)
Change in cash and cash equivalents included in discontinued operations (0.1) 
 3.3
Change in cash and cash equivalents from continuing operations 151.3
 (75.2) 27.2
Cash and cash equivalents at beginning of period 97.6
 172.8
 145.6
 12.0
 37.2
 248.9
Cash and cash equivalents at end of period $248.9
 $97.6
 $172.8
 $21.0
 $12.0
 $37.2


Operating Cash Flows-Operating cash flows are affected by earnings from our business activities.activities and changes in our operating assets and liabilities. Changes in commodity prices and demand for ONEOK Partners’our services or products, whether because of general economic conditions, changes in supply, changes in demand for the end products that are made with our products or increased competition from other service providers, could affect our earnings and operating cash flows. Our operating cash flows can also be impacted by changes in our natural gas and NGL inventory balances, which are driven primarily by commodity prices, supply, demand and the operation of our assets.


20162019 vs. 20152018 - Cash flows from operating activities, before changes in operating assets and liabilities, were $1.4 billion for 2016, compared with $1.2 billion for 2015. The increase wasincreased $130.4 million due primarily to higher natural gasearnings resulting from volume growth in the Rocky Mountain region, STACK and NGL volumes fromSCOOP areas and the completed capital-growth projectsPermian Basin in our Natural Gas Liquids segment and the Williston Basin and STACK and SCOOP areas in our Natural Gas Gathering and Processing and Natural Gas Liquids segments, new plant connections and increased ethane recovery in the Natural Gas Liquids segment, and higher fees resulting from contract restructuring in the Natural Gas Gathering and Processing segment, offset partially by lower realized commodity prices, as discussed in “Financial Results and Operating Information.” Distributions received from unconsolidated affiliates also increased, due primarily to Overland Pass Pipeline.


The changes in operating assets and liabilities decreased operating cash flows $42.5$163.9 million for 2016,2019, compared with a decreasean increase of $149.0$206.4 million for 2015.2018. This change is due primarily to the change in the fair value of our risk-management assets and liabilities; the change in accounts receivable, accounts payable, and other accruals and deferrals resulting from the timing of receipt of cash from customers and payments to vendors, suppliers and suppliers,other third parties; and the change in natural gas and NGLs in storage, which vary both from period to period and vary with the changes in commodity prices, and the change in commodity imbalances, offset partially by the change in risk-management assets and liabilities related to interest-rate swaps.prices.

2015 vs. 2014 - Cash flows from operating activities, before changes in operating assets and liabilities, were $1.16 billion in 2015, compared with $1.23 billion in 2014. The decrease was due primarily to higher interest expense and operating costs, offset partially by higher operating income provided by revenues less cost of sales and fuel at ONEOK Partners, as discussed in “Financial Results and Operating Information.” Distributions received from unconsolidated affiliates also increased, due primarily to Overland Pass Pipeline.

The changes in operating assets and liabilities decreased operating cash flows by $149.0 million in 2015, compared with an increase of $58.3 million in 2014. The change is due primarily to the change in accounts receivable and accounts payable resulting from the timing of receipt of cash from customers and payments to vendors and suppliers, which vary from period to period and vary with changes in commodity prices. In the first quarter 2015, ONEOK Partners also paid $55.1 million to settle forward-starting interest-rate swaps in connection with its March 2015 debt offering.


Investing Cash Flows


20162019 vs. 20152018 - Cash used in investing activities decreased $575.3 million due primarily to lower capital spending as a result of ONEOK Partners’ spending reductions to align with customer needs and projects placed in service, higher proceeds received from sale of assets and higher distributions received from Northern Border Pipeline and Overland Pass Pipeline, offset partially by higher contributions made by ONEOK Partners to Roadrunner.

2015 vs. 2014 - Cash used in investing activities decreased $1.4increased $1.7 billion due primarily to the completion of growth projects at ONEOK Partners, the West Texas LPG acquisition in 2014 and the timing ofincreased capital expenditures for ONEOK Partners’ growth projects in the Natural Gas Gathering and Processing and Natural Gas Liquids segments, offset partially by ONEOK Partners’ contributionsrelated to Roadrunner in 2015.our capital-growth projects.
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Financing Cash Flows


20162019 vs. 20152018 - Cash used infrom financing activities was $584.8 million in 2016, compared with cash provided by financing activities of $108.5 million in 2015, a decrease of approximately $693 million,increased $1.9 billion due primarily to ONEOK Partners repaymentissuances of $1.1$3.25 billion ofin senior unsecured notes, $100the $700 million increase in distributions paid due to a higher number of units outstandingnet draw on our $1.5 Billion Term Loan Agreement and no equity issuances in 2016. These differences were offset partially by an increase in proceeds from short-term borrowings, and drawing on the Term Loan Agreement.

2015 vs. 2014 - Cash provided by financing activities decreased $1.2 billion due primarily to repayment of short-term borrowings at ONEOK Partners, increased distributions from ONEOK Partners to noncontrolling interests and increased ONEOK dividends. Additionally, ONEOK and ONEOK Partners combined raised capital of approximately $1.7 billion through both debt and equity issuances, net of ONEOK’s purchase of additional common units in ONEOK Partners, compared with approximately $2.3 billion in 2014, which includes senior notes issued by ONE Gas in January 2014, which at the time was our consolidated subsidiary. These were offset partially by repaymentsa decrease due to issuances of long-term debt of approximately $7.7 millioncommon stock in 2015,2018.

Cash Flow Analysis for the Year Ended December 31, 2018 vs. 2017 - The cash flow analysis for the year ended December 31, 2018, compared with approximately $557.7 millionthe year ended December 31, 2017, is included in 2014,Part II, Item 7, Management’s Discussion and ONEOK’s repaymentAnalysis of approximately $564.5 millionFinancial Condition and Results of commercial paper in 2014 with proceeds received from ONE Gas.Operations of our 2018 Annual Report on Form 10-K, which is available via the SEC’s website at www.sec.gov and our website at www.oneok.com.


IMPACT OF NEW ACCOUNTING STANDARDS


Information about the impact of new accounting standards is included in Note Aof the Notes to Consolidated Financial Statements in this Annual Report.


ESTIMATES AND CRITICAL ACCOUNTING POLICIES


The preparation of our consolidated financial statementsConsolidated Financial Statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements.Consolidated

Financial Statements. These estimates and assumptions also affect the reported amounts of revenue and expenses during the reporting period. Although we believe these estimates and assumptions are reasonable, actual results could differ from our estimates.


The following is a summary of our most critical accounting policies, which are defined as those estimates and policies most important to the portrayal of our financial condition and results of operations and requiring management’s most difficult, subjective or complex judgment, particularly because of the need to make estimates concerning the impact of inherently uncertain matters. We have discussed the development and selection of our estimates and critical accounting policies with the Audit Committee of our Board of Directors.


Derivatives and Risk-ManagementRisk-management Activities- We utilize derivatives to reduce our market-risk exposure to commodity price and interest-rate fluctuations and to achieve more predictable cash flows. Our commodity price risk includes basis risk, which is the difference in price between various locations where commodities are purchased and sold. We record all derivative instruments at fair value, except for normal purchases and normal sales transactions that are expected to result in physical delivery. Many of the contracts in our derivative portfolio are executed in liquid markets where price transparency exists.

Our fair value measurements classified as Level 3 are composed predominantly of exchange-cleared and over-the-counter derivatives to hedge NGL price risk and natural gas basis risk between various transaction locations and the NYMEX Henry Hub. These measurements are based on inputs that may include one or more unobservable inputs, including internally developed commodity price curves, that incorporate market data from broker quotes and third-party pricing services. Our commodity derivatives are generally valued using forward quotes provided by third-party pricing services that are validated with other market data. We believe any measurement uncertainty at December 31, 2019, is immaterial as our Level 3 fair value measurements are based on unadjusted pricing information from broker quotes and third-party pricing services.

The accounting for changes in the fair value of a derivative instrument depends on whether it qualifies and has been designated as part of a hedging relationship. When possible, we implement effective hedging strategies using derivative financial instruments that qualify as hedges for accounting purposes. We have not used derivative instruments for trading purposes.

For a derivative designated as a cash flow hedge, the effective portion of the gain or loss from a change in fair value of the derivative instrument is deferred in accumulated other comprehensive income (loss) until the forecasted transaction affects earnings, at which time the fair value of the derivative instrument is reclassified into earnings. The ineffective portion of the gain or loss on a derivative instrument designated as a cash flow hedge is recognized in earnings.


We assess the effectiveness of hedging relationships quarterlyat the inception of the hedge by performing an effectiveness test on our hedging relationships to determine whether they are highly effective on a retrospective and prospective basis.effective. We subsequently assess qualitative factors. We do not believe that changes in our fair value estimates of our derivative instruments have a material impact on our results of operations, as the majority of our derivatives are accounted for as effective cash flow hedges for which ineffectiveness is not material.hedges. However, if a derivative instrument is ineligible for cash flow hedge accounting or if we fail to appropriately designate it as a cash flow hedge, changes in fair value of the derivative instrument would be recorded currently in earnings. Additionally, if a cash flow hedge ceases to qualify for hedge accounting treatment because it is no longer probable that the forecasted transaction will occur, the change in fair value of the derivative instrument would be recognized in earnings. For more information on commodity price sensitivity and a discussion of the market risk of pricing changes, see Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

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See Notes CA, B and DC of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of fair value measurements and derivatives and risk-management activities.


Impairment of Goodwill and Long-Lived Assets, includingIncluding Intangible Assets -We assess our goodwill and indefinite-lived intangible assets for impairment at least annually on July 1, unless events or changes in circumstances indicate an impairment may have occurred before that time. As the commodity price environment has remained relatively low since 2015, we elected to perform a quantitative assessment, or Step 1 analysis, to test our goodwill for impairment. The assessment included our current commodity price assumptions, expected contractual terms, anticipated operating costs and volume estimates. Our goodwill impairment analysis performed as of July 1, 2016, did not result in an impairment charge nor did our analysis reflect any reporting units at risk. In each reporting unit, the fair value substantially exceeded the carrying value. Subsequent to that date, no event has occurred indicating that the implied fair value of each of our reporting units is less than the carrying value of its net assets.

As part of our goodwill impairment test, we may first assess qualitative factors (including macroeconomic conditions, industry and market considerations, cost factors and overall financial performance) to determine whether it is more likely than not that the fair value of each of our reporting units is less than its carrying amount. If further testing is necessary or a quantitative test is elected, we perform a two-step impairment test for goodwill. In

Update - Upon adoption of ASU 2017-04 in January 2020, the first step, an initial assessment is made by comparing the fair value of a reporting unit with its book value, including goodwill. If the fair value is less than the book value, an impairment is indicated, and we must perform a second testrequirement to measure the amount of the impairment. In the second test, we calculate the implied fair value of goodwill under the goodwill by deducting the fair value of all tangible and intangible net assetstwo-step impairment test was eliminated. See Note A of the Notes to Consolidated Financial Statements in this Annual Report for more information.

Our qualitative goodwill impairment analysis performed as of July 1, 2019, did not result in an impairment charge nor did our analysis reflect any reporting unit from the fair value determined in step one of the assessment. If the carrying value of the goodwill exceedsunits at risk, and subsequent to that date, no event has occurred indicating that the implied fair value of the goodwill, we will record an impairment charge.

To estimate the fair valueeach of our reporting units we use two generally accepted valuation approaches, an income approach and a market approach, using assumptions consistent with a market participant’s perspective. Underis less than the income approach, we use anticipated cash flows over a periodcarrying value of years plus a terminal value and discount these amounts to their present value using appropriate discount rates. Under the market approach, we apply EBITDA multiples to forecasted EBITDA. The multiples used are consistent with historical asset transactions. The forecasted cash flows are based on average forecasted cash flows for a reporting unit over a period of years.its net assets.


The following table sets forth our goodwill, by segment, for the periods indicated:
December 31,
2016
 December 31,
2015
December 31,
2019
 December 31,
2018
(Thousands of dollars)
(Thousands of dollars)
Natural Gas Gathering and Processing$122,291
 $122,291
$153,404
 $153,404
Natural Gas Liquids268,544
 268,544
371,217
 371,217
Natural Gas Pipelines134,700
 134,700
156,375
 156,479
Total goodwill$525,535
 $525,535
$680,996
 $681,100

As part of our indefinite-lived intangible asset impairment test, we first assess qualitative factors similar to those considered in the goodwill impairment test to determine whether it is more likely than not that the indefinite-lived intangible asset is impaired. If further testing is necessary, we compare the estimated fair value of our indefinite-lived intangible asset with its book value. The fair value of our indefinite-lived intangible asset is estimated using the market approach. Under the market approach, we apply multiples to forecasted cash flows of the assets associated with our indefinite-lived intangible asset. The multiples used are consistent with historical asset transactions. After assessing qualitative and quantitative factors, we determined that there were no impairments to our indefinite-lived intangible asset in 2016.


We assess our long-lived assets, including intangible assets with finite useful lives, for impairment whenever events or changes in circumstances indicate that an asset’s carrying amount may not be recoverable. An impairment is indicated if the carrying amount of a long-lived asset exceeds the sum of the undiscounted future cash flows expected to result from the use and eventual disposition of the asset. If an impairment is indicated, we record an impairment loss equal to the difference between the carrying value and the fair value of the long-lived asset.


For the investments we account for under the equity method, the impairment test considers whether the fair value of the equity investment as a whole, not the underlying net assets, has declined and whether that decline is other than temporary. Therefore, we periodically reevaluateevaluate the amount at which we carry our equity-method investments to determine whether current events or circumstances warrant adjustments to our carrying value.
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Impairment Charges - ONEOK PartnersWe recorded $264.3 million and $76.4$20.2 million of noncash impairment charges primarilyin 2017 related to itscertain nonstrategic long-lived assets and equity investments in the dry natural gas area of the Powder River Basin in 2015North Dakota and 2014, respectively.Oklahoma.


Our impairment tests require the use of assumptions and estimates such as industry economic factors and the profitability of future business strategies. If actual results are not consistent with our assumptions and estimates or our assumptions and estimates change due to new information, we may be exposed to future impairment charges.


See Notes A, D, E F and NM of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of goodwill, long-lived assets and investments in unconsolidated affiliates.


PensionDepreciation Methods and Postretirement Employee Benefits Estimated Useful Lives of Property, Plant and Equipment -WeOur property, plant and equipment are depreciated using the straight-line method that incorporates management assumptions regarding useful economic lives and residual values. As we continue to increase capital spending and place additional assets in service, our estimates related to depreciation expense have become more significant and changes in estimated useful lives of our assets could have a defined benefit retirement plan covering certain full-time employees. We sponsor welfare plansmaterial effect on our results of operations. At the time we place our assets in service, we believe such assumptions are reasonable; however, circumstances may develop that provide postretirement medical and life insurance benefitswould cause us to certain employees who retire with at least five yearschange these assumptions, which would change our depreciation expense prospectively. Examples of service. The expense and liability related to these plans is calculated using statistical and other factors that attempt to anticipate future events. These factorssuch circumstances include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, age and employment periods. In determining the projected benefit obligations and costs, assumptions can change from period to period and may result in material changes in (i) competition, (ii) laws and regulations that limit the costsestimated economic life of an asset, (iii) technology that render an asset obsolete, (iv) expected salvage values and liabilities we recognize. (v) forecasts of the remaining economic life for the resource basins where our assets are located, if any.

See Note LD of the Notes to Consolidated Financial Statements in this Annual Report for additional information.discussion of property, plant and equipment.


During 2016, we recorded net periodic benefit costs of $17.2 million related to our defined benefit pension and postretirement benefits plans in continuing operations.

We estimate that in 2017, we will record net periodic benefit costs of $18.4 million related to our defined benefit pension and postretirement benefits plans.

The following table sets forth the weighted-average assumptions used to determine our estimated 2017 net periodic benefit cost related to our defined benefit pension plans, and sensitivity to changes with respect to these assumptions.
  Rate Used 
Cost
Sensitivity (a)
 
Obligation
Sensitivity (b)
    
(Millions of dollars)
Discount rate 4.5% $1.5
 $13.7
Expected long-term return on plan assets 7.75% $0.7
 $
(a)Contingencies - Approximate impact a quarter percentage point decrease in the assumed rate would have on net periodic pension costs.
(b) - Approximate impact a quarter percentage point decrease in the assumed rate would have on defined benefit pension obligation.

A quarter percentage point change in either of the assumed rates would not have a significant impact on our postretirement benefit plan costs or obligation. Assumed health care cost-trend rates have an effect on the amounts reported for our postretirement benefit plans. A one percentage point change in assumed health care cost trend rates would have the following effects:
  
One Percentage
Point Increase
 
One Percentage
Point Decrease
  
(Millions of dollars)
Effect on total of service and interest cost $0.2
 $(0.2)
Effect on postretirement benefit obligation $1.0
 $(0.9)

During 2016, we made no contributions to our defined benefit pension plan and $1.0 million in contributions to our postretirement benefit plans. We contributed $7.5 million to our defined benefit pension plan in January 2017, and we expect to make approximately $2.0 million in contributions to our postretirement plans in 2017.

Contingencies -Our accounting for contingencies covers a variety of business activities, including contingencies for legal and environmental exposures. We accrue these contingencies when our assessments indicate that it is probable that a liability has been incurred or an asset will not be recovered, and an amount can be reasonably estimated. We expense legal fees as incurred and base our legal liability estimates on currently available facts and our assessments of the ultimate outcome or resolution. Accruals for estimated losses from environmental remediation obligations generally are recognized no later than the completion of a remediation feasibility study. Recoveries of environmental remediation costs from other parties are recorded as assets
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when their receipt is deemed probable. Our expenditures for environmental evaluation, mitigation, remediation and compliance to date have not been significant in relation to our financial position or results of operations, and our expenditures related to environmental matters had no material effect on earnings or cash flows during 2016, 20152019, 2018 or 2014.2017. Actual results may differ from our estimates resulting in an impact, positive or negative, on earnings.our results of operations.


See Note PN of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of contingencies.


CONTRACTUAL OBLIGATIONS AND COMMERCIAL COMMITMENTS


The following table sets forth our contractual obligations related to debt, operating leases and other long-term obligations as of December 31, 2016.2019. For additional discussion of the debt and lease agreements, see Note GNotes F and O of the Notes to the Consolidated Financial Statements in this Annual Report. The table below includes the contractual obligations of our former energy services business as ONEOK remains responsible for those obligations.
 Payments Due by Period Payments Due by Period
Contractual Obligations Total 2017 2018 2019 2020 2021 Thereafter Total 2020 2021 2022 2023 2024 Thereafter
ONEOK 
(Millions of dollars)
Long-term debt $1,634.5
 $3.0
 $3.0
 $3.0
 $3.0
 $3.0
 $1,619.5
 
(Millions of dollars)
Senior notes $11,322.4
 $
 $
 $1,447.4
 $925.0
 $500.0
 $8,450.0
Commercial paper borrowings 220.0
 220.0
 
 
 
 
 
$1.5 Billion Term Loan Agreement 1,250.0
 
 1,250.0
 
 
 
 
Guardian Pipeline senior notes 21.3
 7.7
 7.7
 5.9
 
 
 
Interest payments on debt 944.3
 97.2
 97.0
 96.8
 96.6
 96.4
 460.3
 8,754.2
 610.2
 601.2
 530.8
 487.2
 442.5
 6,082.3
Operating leases 1.3
 0.6
 0.5
 0.2
 
 
 
 19.6
 2.5
 2.1
 2.0
 1.9
 1.9
 9.2
Energy Services firm transportation and storage contracts 17.4
 9.7
 4.0
 0.9
 0.9
 0.7
 1.2
Employee benefit plans 67.3
 9.5
 14.6
 14.5
 13.8
 14.9
 
ONEOK total $2,664.8
 $120.0
 $119.1
 $115.4
 $114.3
 $115.0
 $2,081.0
ONEOK Partners  
  
  
  
  
  
  
ONEOK Partners senior notes $5,700.0
 $400.0
 $425.0
 $500.0
 $300.0
 $
 $4,075.0
Term Loan Agreement 1,000.0
 
 
 1,000.0
 
 
 
Guardian Pipeline senior notes 44.3
 7.7
 7.7
 7.7
 7.7
 7.7
 5.8
Commercial paper borrowings 1,110.3
 1,110.3
 
 
 
 
 
Interest payments on debt 4,009.5
 322.5
 314.5
 243.0
 233.2
 222.5
 2,673.8
Operating leases 15.0
 2.0
 1.9
 1.6
 1.5
 1.4
 6.6
Finance lease 39.6
 4.5
 4.5
 4.5
 4.5
 4.5
 17.1
Firm transportation and storage contracts 227.1
 51.5
 43.0
 37.5
 37.1
 23.0
 35.0
 398.4
 61.6
 48.1
 40.1
 36.4
 34.3
 177.9
Financial and physical derivatives 193.0
 193.0
 
 
 
 
 
 188.1
 168.0
 20.1
 
 
 
 
Purchase commitments, rights of way and other 296.7
 88.3
 88.7
 45.5
 45.5
 20.5
 8.2
ONEOK Partners total $12,595.9
 $2,175.3
 $880.8
 $1,835.3
 $625.0
 $275.1
 $6,804.4
Employee benefit plans 81.8
 14.1
 14.6
 13.1
 14.5
 13.8
 11.7
Purchase commitments and other 312.7
 54.1
 53.9
 53.2
 50.8
 37.8
 62.9
Total $15,260.7
 $2,295.3
 $999.9
 $1,950.7
 $739.3
 $390.1
 $8,885.4
 $22,608.1
 $1,142.7
 $2,002.2
 $2,097.0
 $1,520.3
 $1,034.8
 $14,811.1


Long-term debt, ONEOK Partners seniorSenior notes, $1.5 Billion Term Loan Agreement Guardian Pipeline senior notes and commercial paper borrowings - TheRepresents the amount of principal due in each period.


Interest payments on debt - Interest payments are calculated by multiplying long-term debt principal amount by the respective coupon rates.


Operating leases - Our operating leases primarily include leases for certain buildings, warehouses, office space, pipeline capacity, land and equipment, including pipeline equipment, rail cars and information technology equipment. As of December 31, 2019, we entered into an additional operating lease that had not yet commenced with total lease payments of $87.8 million over a lease term of 10 years, which is excluded from our table above.


Finance lease - We lease certain compression facilities under a finance lease that has a fixed-price purchase option in 2028.

Firm transportation and storage contracts - TheOur Natural Gas Gathering and Processing and Natural Gas Liquids segments are party to fixed-price contracts for firm transportation and storage capacity.


Energy services firm transportation and storage contracts - These obligations include future payments related to released contracts. See additional information in Note Q in the Notes to the Consolidated Financial Statements.

Financial and physical derivatives - These are obligations arising from ONEOK Partners’our fixed- and variable-price purchase commitments for physical and financial commodity derivatives. Estimated future variable-price purchase commitments are based on market information at December 31, 2016.2019. Actual future variable-price purchase obligations may vary depending on market prices at the time of delivery. Sales of the related physical volumes and net positive settlements of financial derivatives are not reflected in the table above.
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Employee benefit plans - We contributed $7.5$12.1 million to our defined benefit pension plan in January 20172020 and expect to make approximately $2.0 million in contributions to our other postretirement plans in 2017.2020. See Note LK of the Notes to Consolidated Financial Statements in this Annual Report for discussion of our employee benefit plans.


Purchase commitments rights of way and other - Purchase commitments include commitments related to ONEOK Partners’our growth capital expenditures and other rights-of-way and contractual commitments. Purchase commitments exclude commodity purchase contracts, which are included in the “Financial and physical derivatives” amounts.


FORWARD-LOOKING STATEMENTS


Some of the statements contained and incorporated in this Annual Report are forward-looking statements as defined under federal securities laws. The forward-looking statements relate to our anticipated financial performance (including projected operating income, net income, capital expenditures, cash flowflows and projected levels of dividends and distributions)dividends), liquidity, management’s plans and objectives for our future growthcapital-growth projects and other future operations (including plans to construct additional

natural gas and natural gas liquidsNGL pipelines, processing and processingfractionation facilities and related cost estimates), our business prospects, the outcome of regulatory and legal proceedings, market conditions and other matters. We make these forward-looking statements in reliance on the safe harbor protections provided under federal securities legislation and other applicable laws. The following discussion is intended to identify important factors that could cause future outcomes to differ materially from those set forth in the forward-looking statements.


Forward-looking statements include the items identified in the preceding paragraph, the information concerning possible or assumed future results of our operations and other statements contained or incorporated in this Annual Report identified by words such as “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “project,“forecast,” “goal,” “guidance,” “intend,” “may,” “might,” “outlook,” “plan,” “believe,“potential,” “project,” “scheduled,” “should,” “goal,“will,“forecast,‘would, “guidance,” “could,” “may,” “continue,” “might,” “potential,” “scheduled” and other words and terms of similar meaning.


One should not place undue reliance on forward-looking statements. Known and unknown risks, uncertainties and other factors may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by forward-looking statements. Those factors may affect our operations, markets, products, services and prices. In addition to any assumptions and other factors referred to specifically in connection with the forward-looking statements, factors that could cause our actual results to differ materially from those contemplated in any forward-looking statement include, among others, the following:
the impact on drilling and production by factors beyond our control, including the demand for natural gas and crude oil; producers’ desire and ability to drill and obtain necessary permits; regulatory compliance; reserve performance; and capacity constraints on the requisite approvalspipelines that transport crude oil, natural gas and NGLs from producing areas and our shareholdersfacilities;
risks associated with adequate supply to our gathering, processing, fractionation and pipeline facilities, including production declines that outpace new drilling or ONEOK Partners’ unitholders relating to the Merger Transaction;
the risk that we or ONEOK Partners may be unable to obtain governmental and regulatory approvals required for the Merger Transaction, if any, or required governmental and regulatory approvals, if any, may delay the Merger Transaction or result in the impositionextended periods of conditions that could cause the parties to abandon the Merger Transaction;
the risk that a condition to closing of the Merger Transaction may not be satisfied;
the timing to consummate the Merger Transaction;
the risk that cost savings, tax benefits and any other synergies from the Merger Transaction may not be fully realized or may take longer to realize than expected;
disruption from the Merger Transaction may make it more difficult to maintain relationships with customers, employees or suppliers;
the possible diversion of management time on Merger Transaction-related issues;
the impact and outcome of pending and future litigation, including litigation, if any, relating to the Merger Transaction;
the effects of weather and other natural phenomena, including climate change, on our operations, demand for our services and energy prices;ethane rejection;
competition from other United States and foreign energy suppliers and transporters, as well as alternative forms of energy, including, but not limited to, solar power, wind power, geothermal energy and biofuels such as ethanol and biodiesel;
demand for our services and products in the capital intensive natureproximity of our businesses;
the profitability of assets or businesses acquired or constructed by us;
our ability to make cost-saving changes in operations;
risks of marketing, trading and hedging activities, including the risks of changes in energy prices or the financial condition of our counterparties;
the uncertainty of estimates, including accruals and costs of environmental remediation;
the timing and extent of changes in energy commodity prices;
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the effects of changes in governmental policies and regulatory actions, including changes with respect to income and other taxes, pipeline safety, environmental compliance, climate change initiatives and authorized rates of recovery of natural gas and natural gas transportation costs;
the impact on drilling and production by factors beyond our control, including the demand for natural gas and crude oil; producers’ desire and ability to obtain necessary permits; reserve performance; and capacity constraints on the pipelines that transport crude oil, natural gas and NGLs from producing areas and our facilities;
difficulties or delays experienced by trucks, railroads or pipelines in delivering products to or from our terminals or pipelines;
changes in demand for the use of natural gas, NGLs and crude oil because of market conditions caused by concerns about climate change;
conflicts of interest between us, ONEOK Partners and related parties of ONEOK Partners;
the impact of unforeseen changes in interest rates, equity markets, inflation rates, economic recession and other external factors over which we have no control, including the effect on pension and postretirement expense and funding resulting from changes in equity and bond market returns;
our indebtedness could make us vulnerable to general adverse economic and industry conditions, limit our ability to borrow additional funds and/or place us at competitive disadvantages compared with our competitors that have less debt, or have other adverse consequences;
actions by rating agencies concerning the credit ratings of ONEOK and ONEOK Partners;
the results of administrative proceedings and litigation, regulatory actions, rule changes and receipt of expected clearances involving any local, state or federal regulatory body, including the FERC, the National Transportation Safety Board, the PHMSA, the EPA and CFTC;
our ability to access capital at competitive rates or on terms acceptable to us;
risks associated with adequate supply to our gathering, processing, fractionation and pipeline facilities, including production declines that outpace new drilling or extended periods of ethane rejection;
the risk that material weaknesses or significant deficiencies in our internal controls over financial reporting could emerge or that minor problems could become significant;
the impact and outcome of pending and future litigation;
the ability to market pipeline capacity on favorable terms, including the effects of:
future demand for and prices of natural gas, NGLs and crude oil;
competitive conditions in the overall energy market;
availability of supplies of Canadian and United States natural gas and crude oil; and
availability of additional storage capacity;
performancethe effects of contractual obligations byweather and other natural phenomena, including climate change, on our customers, service providers, contractorsoperations, demand for our services and shippers;energy prices;
acts of nature, sabotage, terrorism or other similar acts that cause damage to our facilities or our suppliers’, customers’ or shippers’ facilities;
the possibility of future terrorist attacks or the possibility or occurrence of an outbreak of, or changes in, hostilities or changes in the political conditions throughout the world;
economic climate and growth in the geographic areas in which we do business;
the timing and extent of changes in energy commodity prices;
the timely receipt of approval by applicable governmental entities for construction and operation of our pipeline and other projects and required regulatory clearances;
our ability to acquire all necessary permits, consents or other approvals in a timely manner, to promptly obtain all necessary materials and supplies required for construction, and to construct gathering, processing, storage, fractionation and transportation facilities without labor or contractor problems;
the mechanical integrityprofitability of facilities operated;
demand for our services in the proximity of our facilities;
our ability to control operating costs;
acts of nature, sabotage, terrorismassets or other similar acts that cause damage to our facilitiesbusinesses acquired or our suppliers’ or shippers’ facilities;
economic climate and growth in the geographic areas in which we do business;constructed by us;
the risk of a prolonged slowdown in growth or decline in the United States or international economies, including liquidity risks in United States or foreign credit markets;
risks of marketing, trading and hedging activities, including the risks of changes in energy prices or the financial condition of our counterparties;
the uncertainty of estimates, including accruals and costs of environmental remediation;
changes in demand for the use of natural gas, NGLs and crude oil because of market conditions caused by concerns about climate change;
the impact of recently issueduncontracted capacity in our assets being greater or less than expected;
the composition and future accounting updatesquality of the natural gas and NGLs we gather and process in our plants and transport on our pipelines;
the efficiency of our plants in processing natural gas and extracting and fractionating NGLs;

our ability to control construction costs and completion schedules of our pipelines and other projects;
the effects of changes in accounting policies;governmental policies and regulatory actions, including changes with respect to income and other taxes, pipeline safety, environmental compliance, climate change initiatives and authorized rates of recovery of natural gas and natural gas transportation costs;
the possibilityability to recover operating costs and amounts equivalent to income taxes, costs of future terrorist attacks or the possibility or occurrence of an outbreak of, or changesproperty, plant and equipment and regulatory assets in hostilities or changes in the political conditions in the Middle Eastour state and elsewhere;FERC-regulated rates;
the riskresults of increased costs for insurance premiums, securityadministrative proceedings and litigation, regulatory actions, executive orders, rule changes and receipt of expected clearances involving any local, state or other items as a consequencefederal regulatory body, including the FERC, the National Transportation Safety Board, the PHMSA, the EPA and the CFTC;
difficulties or delays experienced by trucks, railroads or pipelines in delivering products to or from our terminals or pipelines;
the capital-intensive nature of terrorist attacks;our businesses;
the mechanical integrity of facilities operated;
risks associated with pending or possible acquisitions and dispositions, including our ability to finance or integrate any such acquisitions and any regulatory delay or conditions imposed by regulatory bodies in connection with any such acquisitions and dispositions;
the impact of uncontracted capacityrisk that material weaknesses or significant deficiencies in our assets being greaterinternal controls over financial reporting could emerge or less than expected;
the ability to recover operating costs and amounts equivalent to income taxes, costs of property, plant and equipment and regulatory assets in our state and FERC-regulated rates;
the composition and quality of the natural gas and NGLs we gather and process in our plants and transport on our pipelines;
the efficiency of our plants in processing natural gas and extracting and fractionating NGLs;
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that minor problems could become significant;
the impact of potential impairment charges;unforeseen changes in interest rates, debt and equity markets, inflation rates, economic recession and other external factors over which we have no control, including the effect on pension and postretirement expense and funding resulting from changes in equity and bond market returns;
our indebtedness and guarantee obligations could make us vulnerable to general adverse economic and industry conditions, limit our ability to borrow additional funds and/or place us at competitive disadvantages compared with our competitors that have less debt or have other adverse consequences;
actions by rating agencies concerning our credit;
our ability to access capital at competitive rates or on terms acceptable to us;
the impact and outcome of pending and future litigation;
performance of contractual obligations by our customers, service providers, contractors and shippers;
our ability to control operating costs and make cost-saving changes;
the impact of recently issued and future accounting updates and other changes in accounting policies;
the risk of increased costs for insurance premiums, security or other items as a consequence of terrorist attacks;
the risk inherent in the use of information systems in our respective businesses and those of our counterparties and service providers, implementation of new software and hardware, and the impact on the timeliness of information for financial reporting;
our ability to control construction costs and completion schedulesthe impact of our pipelines and other projects;potential impairment charges; and
the risk factors listed in the reports we have filed and may file with the SEC, which are incorporated by reference.


These factors are not necessarily all of the important factors that could cause actual results to differ materially from those expressed in any of our forward-looking statements. Other factors could also have material adverse effects onaffect adversely our future results. These and other risks are described in greater detail in Part I, Item 1A, Risk Factors, in this Annual Report and in our other filings that we make with the SEC, which are available via the SEC’s website at www.sec.gov and our website at www.oneok.com. All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by these factors. Any such forward-looking statement speaks only as of the date on which such statement is made, and other than as required under securities laws, we undertake no obligation to update publicly any forward-looking statement whether as a result of new information, subsequent events or change in circumstances, expectations or otherwise.


ITEM 7A.    QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK


Our exposure to market risk discussed below includes forward-looking statements and represents an estimate of possible changes in future earnings that could occur assuming hypothetical future movements in interest rates or commodity prices. Our views on market risk are not necessarily indicative of actual results that may occur and do not represent the maximum possible gains and losses that may occur since actual gains and losses will differ from those estimated based on actual fluctuations in interest rates or commodity prices and the timing of transactions.


We are exposed to market risk due to commodity price and interest-rate volatility. Market risk is the risk of loss arising from adverse changes in market rates and prices. We may use financial instruments, including forward sales, swaps, options and futures, to manage the risks of certain identifiable or anticipated transactions and achieve a more predictable cash flow.flows. Our risk-management function follows established policies and procedures to monitor ONEOK Partners’our natural gas, condensate and NGL

marketing activities and our and ONEOK Partners’ interest rates to ensure our hedging activities mitigate market risks. Neither we nor ONEOK PartnersWe do not use financial instruments for trading purposes.


We recordSee Note Aof the Notes to Consolidated Financial Statements in this Annual Report for discussion on our accounting policies for our derivative instruments at fair value. We estimateand the fair value of derivative instruments using available market information and appropriate valuation techniques. Changes in derivative instruments’ fair values are recognized in earnings unless the instrument qualifies as a hedge and meets specific hedge accounting criteria. The effective portion of qualifying derivative instruments’ gains and losses may offset the hedged items’ related results in earnings for a fair value hedge or be deferred in accumulated other comprehensive income (loss) for a cash flow hedge.impact on our Consolidated Financial Statements.


COMMODITY PRICE RISK


As part of itsour hedging strategy, ONEOK Partners useswe use commodity derivative financial instruments and physical-forward contracts described in Note DC of the Notes to Consolidated Financial Statements in this Annual Report to minimizereduce the impact of near-term price fluctuations related toof natural gas, NGLs and condensate.


ONEOK Partners is exposed to basis risk between the various production and market locations where it receives and sells commodities. Although ONEOK Partners’our businesses are predominatelyprimarily fee-based, in theour Natural Gas Gathering and Processing segment, ONEOK Partners iswe are exposed to commodity price risk as a result of retaining a portion of the commodity sales proceeds associated with itsour POP with fee contracts. ONEOK Partners has restructured a portion of its POP with fee contracts to include significantly higher fees, which reduces its equity volumes and the related commodity price exposure. However, underUnder certain POP with fee contracts, ONEOK Partners’ fee revenuesour contractual fees and POP percentage may increase or decrease if production volumes, delivery pressures or commodity prices change relative to specified thresholds. We are exposed to basis risk between the various production and market locations where we buy and sell commodities.


The following tables set forth hedging information for theour Natural Gas Gathering and Processing segment’s forecasted equity volumes for the periods indicated:
Year Ending December 31, 2017 Year Ending December 31, 2020
Volumes
Hedged
 Average Price 
Percentage
Hedged
 
Volumes
Hedged
 Average Price 
Percentage
Hedged
NGLs - excluding ethane (MBbl/d) - Conway/Mont Belvieu
8.0
 $0.51
/ gallon 91% 10.3
 $0.55
/ gallon 63%
Condensate (MBbl/d) - WTI-NYMEX
1.8
 $44.88
/ Bbl 72% 3.0
 $54.08
/ Bbl 62%
Natural gas (BBtu/d) - NYMEX and basis
73.1
 $2.63
/ MMBtu 97% 125.0
 $2.39
/ MMBtu 76%
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 Year Ending December 31, 2018
 
Volumes
Hedged
 Average Price 
Percentage
Hedged
NGLs - excluding ethane (MBbl/d) - Conway/Mont Belvieu
1.9
 $0.68
/ gallon 22%
Condensate (MBbl/d) - WTI-NYMEX
0.6
 $56.80
/ Bbl 25%
Natural gas (BBtu/d) - NYMEX and basis
49.7
 $2.80
/ MMBtu 74%
  Year Ending December 31, 2021
  
Volumes
Hedged
 Average Price 
Percentage
Hedged
Natural gas (BBtu/d) - NYMEX and basis
 36.4
 $2.43
/ MMBtu 19%


TheOur Natural Gas Gathering and Processing segment’s commodity price sensitivity is estimated as a hypothetical change in the price of NGLs, crude oil and natural gas at December 31, 2016.2019. Condensate sales are typically based on the price of crude oil. WeAssuming normal operating conditions, we estimate the following for ONEOK Partners’our forecasted equity volumes, including the effects of hedging information set forth above, and assuming normal operating conditions, for the year ending December 31, 2017:volumes:
a $0.01 per-gallonper gallon change in the composite price of NGLs, excluding ethane, would change 12-month adjusted EBITDA for the yearyears ending December 31, 2017,2020 and 2021, by approximately $0.4 million;$2.5 million and $3.0 million, respectively;
a $1.00 per-barrelper barrel change in the price of crude oil would change 12-month adjusted EBITDA for the yearyears ending December 31, 2017,2020 and 2021, by approximately $0.4 million;$1.5 million and $1.8 million, respectively; and
a $0.10 per-MMBtuper MMBtu change in the price of residue natural gas would change 12-month adjusted EBITDA for the yearyears ending December 31, 2017,2020 and 2021, by approximately $0.1 million.$6.1 million and $7.1 million, respectively.


These estimates do not include any effects of hedging or effects on demand for ONEOK Partners’our services or natural gas processing plant operations that might be caused by, or arise in conjunction with, commodity price fluctuations. For example, a change in the gross processing spread may cause a change in the amount of ethane extracted from the natural gas stream, impacting gathering and processing financial results for certain contracts.

The following tables set forth hedging information related to purchased put options to reduce commodity price sensitivity associated with certain POP with fee contracts:
  Year Ending December 31, 2017
  
Volumes
Hedged
 Average Strike Price 
Fair Value Asset at
December 31, 2016
       
(Millions of dollars)
Natural gas (BBtu/d) - NYMEX
 147.9
 $2.47
/ MMBtu $1.0

See Note D of the Notes to Consolidated Financial Statements in this Annual Report for more information on ONEOK Partners’ hedging activities.


INTEREST-RATE RISK


We and ONEOK Partners are exposed to interest-rate risk through the ONEOKborrowings under our $2.5 Billion Credit Agreement, the ONEOK Partners Credit$1.5 Billion Term Loan Agreement, ONEOK Partners’ commercial paper program Term Loan Agreement and long-term debt issuances. Future increases in LIBOR corporateor the established replacement rate, commercial paper rates or investment-grade corporate bond rates could expose us to increased interest costs on future borrowings. We manage interest-rate risk through the use of fixed-rate debt, floating-rate debt and interest-rate swaps. Interest-rate swaps are agreements to exchange interest payments at some future point based on specified notional amounts. In January 2016, ONEOK Partners2019, we entered into interest-rate swaps with notional amounts totaling $1 billion to hedge the variability$625 million of its LIBOR-based interest payments, all of which were active swaps as of December 31, 2016. In addition, in June 2016, ONEOK Partners entered into forward-starting interest-rate swaps with notional amounts totaling $750 million to hedge the variability of interest payments on a portion of itsour forecasted debt issuances that may result from changes in the benchmark interest rate before the debt is issued, resultingissued. We also settled $1.8

billion of our forward-starting interest-rate swaps related to our underwritten public offering of $1.25 billion senior unsecured notes in totalMarch 2019 and $2.0 billion senior unsecured notes in August 2019.

At December 31, 2019 and 2018, we had forward-starting interest-rate swaps with notional amounts totaling $1.8 billion and $3.0 billion, respectively, to hedge the variability of this typeinterest payments on a portion of interest-rate swap of $1.2 billion atour forecasted debt issuances. At December 31, 2016, compared2019 and 2018, we had interest-rate swaps with $400 million at December 31, 2015.notional amounts totaling $1.3 billion to hedge the variability of our LIBOR-based interest payments. All of ONEOK Partners’our interest-rate swaps are designated as cash flow hedges. At December 31, 2016, ONEOK Partners2019, we had derivative assets of $47.5$0.6 million and derivative liabilities of $12.8$201.9 million related to these interest-rate swaps. At December 31, 2015, ONEOK Partners2018, we had derivative assets of $19.0 million and derivative liabilities of $9.9$99.3 million related to these interest-rate swaps.


See Note DC of the Notes to Consolidated Financial Statements in this Annual Report for more information on ONEOK Partners’our hedging activities.


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COUNTERPARTY CREDIT RISK


ONEOK and ONEOK PartnersWe assess the creditworthiness of theirour counterparties on an ongoing basis and require security, including prepayments and other forms of collateral, when appropriate. Certain of ONEOK Partners’our counterparties to the Natural Gas Gathering and Processing segment’s natural gas sales, the Natural Gas Liquids segment’s marketing activities and the Natural Gas Pipelines segment’s storage activities may be impacted by thea relatively low commodity price environment and could experience financial problems, which could result in nonpayment and/or nonperformance, which could impact adversely impact our results of operations.


Customer concentration - In 2016,2019, no single customer represented more than 10 percent10% of our consolidated revenues and only 26 customers individually represented one percent or more of our consolidated revenues, the majority of which are investment-grade customers, as rated by S&P, Moody’s or our comparable internal ratings, or secured by letters of credit or other collateral.revenues.


Natural Gas Gathering and Processing - TheOur Natural Gas Gathering and Processing segment’s customers aresegment derives services revenue primarily from major and independent crude oil and natural gas producers, which include both large integrated and independent exploration and production companies. ONEOK Partners isIn this segment, our downstream commodity sales customers are primarily utilities, large industrial companies, marketing companies and our NGL affiliate. We are not typically exposed to material credit risk with exploration and production customersproducers under POP with fee contracts as ONEOK Partners sellswe sell the commodities and remitsremit a portion of the sales proceeds back to the producer customer.less our contractual fees. In 20162019 and 2015,2018, approximately 99 percent90% and 95%, respectively, of the downstream commodity sales in theour Natural Gas Gathering and Processing segment were made to investment-grade customers, as rated by S&P, Moody’s or our comparable internal ratings, or were secured by letters of credit or other collateral.


Natural Gas Liquids - TheOur Natural Gas Liquids segment’s customerscounterparties are primarily NGL and natural gas gathering and processing companies; largemajor and independent crude oil and natural gas production companies; utilities; large industrial companies; natural gasoline distributors; propane distributors; ethanol producers;municipalities; and petrochemical, refining and NGL marketing companies. ONEOK Partners earns fee-based revenue fromWe charge fees to NGL and natural gas gathering and processing customerscounterparties and natural gas liquidsNGL pipeline transportation customers. ONEOK Partners isWe are not typically exposed to material credit risk on the majority of itsour exchange services fee revenues,fees, as ONEOK Partners purchaseswe purchase NGLs from itsour gathering and processing customerscounterparties and deducts feesdeduct our fee from the amounts it remits. ONEOK Partnerswe remit. We also earnsearn sales revenue on the downstream sales of NGL products. In 20162019 and 2015,2018, approximately 80 percent80% of this segment’s commodity sales were made to investment-grade customers, as rated by S&P, Moody’s or our comparable internal ratings, or were secured by letters of credit or other collateral. In addition, the majority of theour Natural Gas Liquids segment’s pipeline tariffs provide ONEOK Partnersus the ability to require security from shippers.


Natural Gas Pipelines - TheOur Natural Gas Pipelines segment’s customers are primarily local natural gas distribution companies, electric-generation facilities, large industrial companies, municipalities, irrigation customersproducers, processors and marketing companies. In 20162019 and 2015,2018, approximately 85 percent85% of theour revenues in this segment were from investment-grade customers, as rated by S&P, Moody’s or our comparable internal ratings, or were secured by letters of credit or other collateral. In addition, the majority of theour Natural Gas Pipelines segment’s pipeline tariffs provide ONEOK Partnersus the ability to require security from shippers.


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ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRMReport of Independent Registered Public Accounting Firm


To the Board of Directors and Shareholders of
ONEOK, Inc.:


In our opinion,Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of ONEOK, Inc. and its subsidiaries (the “Company”) as of December 31, 2019 and 2018, and the related consolidated statements of income, of comprehensive income, shareholders’of changes in equity and cash flows present fairly, in all material respects, the financial position of ONEOK, Inc. and its subsidiaries (the Company)at December 31, 2016 and 2015, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2016,2019, including the related notes (collectively referred to as the “consolidated financial statements”). We also have audited the Company’s internal control over financial reporting as of December 31, 2019, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2019 and 2018, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2019 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2016,2019, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations ofCOSO.

Change in Accounting Principle

As discussed in Notes A and P to the Treadway Commission (COSO). consolidated financial statements, the Company changed the manner in which it accounts for revenue from contracts with customers in 2018.

Basis for Opinions

The Company’s management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Report on Internal Control over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on thesethe Company’s consolidated financial statements and on the Company’s internal control over financial reporting based on our integrated audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States).PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.

Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence supportingregarding the amounts and disclosures in the consolidated financial statements, assessingstatements. Our audits also included evaluating the accounting principles used and significant estimates made by management, andas well as evaluating the overall presentation of the consolidated financial statement presentation.statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.


Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to

permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.


Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.



Critical Audit Matters

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidatedfinancial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Valuation of Level 3 Commodity Derivative Assets and Liabilities

As described in Notes A, B and C to the consolidated financial statements, the Company’s level 3 commodity derivative assets and liabilities total $55.6 million and $24.8 million, respectively, as of December 31, 2019. As disclosed by management, commodity price risk includes basis risk, which is the difference in price between various locations where commodities are purchased and sold. Management records all derivative instruments at fair value, except for normal purchases and normal sales transactions that are expected to result in physical delivery. Many of the contracts in its derivative portfolio are executed in liquid markets where price transparency exists. Fair value measurements classified as Level 3 are comprised predominantly of exchange-cleared and over-the-counter derivatives to hedge NGL price risk and natural gas basis risk between various transaction locations and the NYMEX Henry Hub. These measurements are based on inputs that may include one or more unobservable inputs, including internally developed commodity price curves, that incorporate market data from broker quotes and third-party pricing services. The commodity derivatives are generally valued using forward quotes provided by third-party pricing services that are validated with other market data.

The principal considerations for our determination that performing procedures relating to the valuation of level 3 commodity derivative assets and liabilities is a critical audit matter are there was significant estimation by management to determine the fair value of these derivatives due to the use of internally developed commodity price curves, that incorporate market data from broker quotes and third-party pricing services. This in turn led to a high degree of subjectivity and effort in evaluating audit evidence related to the valuation. In addition, the audit effort involved the use of professionals with specialized skill and knowledge to assist in performing these procedures and evaluating the audit evidence obtained.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to the valuation of level 3 commodity derivative assets and liabilities, including controls over the Company’s model, significant assumptions, and data. These procedures also included, among others, the involvement of professionals with specialized skill and knowledge to assist in developing an independent estimate of the level 3 commodity derivative assets and liabilities and comparison of the independent estimate to management’s estimate. Developing the independent estimate involved testing the completeness and accuracy of data used and evaluating management’s assumptions related to the internally developed commodity price curves.



/s/ PricewaterhouseCoopers LLP


Tulsa, Oklahoma
February 28, 201725, 2020



We have served as the Company’s auditor since 2007.

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ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF INCOME      
  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars, except per share amounts)
Revenues      
Commodity sales $6,858,456
 $6,098,343
 $10,724,981
Services 2,062,478
 1,664,863
 1,470,110
Total revenues 8,920,934
 7,763,206
 12,195,091
Cost of sales and fuel (exclusive of items shown separately below) 6,496,124
 5,641,052
 10,088,548
Operations and maintenance 668,335
 605,748
 599,143
Depreciation and amortization 391,585
 354,620
 294,684
Impairment of long-lived assets (Note E) 
 83,673
 
General taxes 88,849
 87,583
 75,744
Gain on sale of assets (9,635) (5,629) (6,599)
Operating income 1,285,676
 996,159
 1,143,571
Equity in net earnings from investments (Note N) 139,690
 125,300
 117,415
Impairment of equity investments (Note N) 
 (180,583) (76,412)
Allowance for equity funds used during construction 209
 2,179
 14,937
Other income 6,091
 368
 5,598
Other expense (4,059) (4,760) (29,073)
Interest expense (net of capitalized interest of $10,591, $36,572 and $54,813, respectively) (469,651) (416,787) (356,163)
Income before income taxes 957,956
 521,876
 819,873
Income taxes (Note M) (212,406) (136,600) (151,158)
Income from continuing operations 745,550
 385,276
 668,715
Income (loss) from discontinued operations, net of tax (Note Q) (2,051) (6,081) (5,607)
Net income 743,499
 379,195
 663,108
Less: Net income attributable to noncontrolling interests 391,460
 134,218
 349,001
Net income attributable to ONEOK $352,039
 $244,977
 $314,107
Amounts attributable to ONEOK:      
Income from continuing operations $354,090
 $251,058
 $319,714
Income (loss) from discontinued operations (2,051) (6,081) (5,607)
Net income $352,039
 $244,977
 $314,107
Basic earnings per share:      
Income from continuing operations (Note J) $1.68
 $1.19
 $1.53
Income (loss) from discontinued operations (0.01)
(0.02) (0.03)
Net income $1.67
 $1.17
 $1.50
Diluted earnings per share:      
Income from continuing operations (Note J) $1.67
 $1.19
 $1.52
Income (loss) from discontinued operations (0.01) (0.03) (0.03)
Net income $1.66
 $1.16
 $1.49
Average shares (thousands)
      
Basic 211,128
 210,208
 209,391
Diluted 212,383
 210,541
 210,427
Dividends declared per share of common stock $2.46
 $2.43
 $2.125
See accompanying Notes to Consolidated Financial Statements.
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ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME    
   
  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars)
Net income $743,499
 $379,195
 $663,108
Other comprehensive income (loss), net of tax  
  
  
Unrealized gains (losses) on derivatives, net of tax of $5,452, $(6,138) and $10,029, respectively (30,300) 41,362
 (58,307)
Realized (gains) losses on derivatives in net income, net of tax of $230, $8,815 and $(14,098), respectively (6,977) (54,709) 41,723
Unrealized holding gains (losses) on available-for-sale securities, net of tax of $0, $648 and $(106), respectively 
 (955) 98
Change in pension and postretirement benefit plan liability, net of tax of $11,128, $(10,278) and $15,781, respectively (16,693) 15,416
 (23,672)
Other comprehensive income (loss) on investments in unconsolidated affiliates, net of tax of $270, $293 and $0, respectively (1,505) (1,632) 
Total other comprehensive income (loss), net of tax (55,475) (518) (40,158)
Comprehensive income 688,024
 378,677
 622,950
Less: Comprehensive income attributable to noncontrolling interests 363,093
 124,589
 326,598
Comprehensive income attributable to ONEOK $324,931
 $254,088
 $296,352
See accompanying Notes to Consolidated Financial Statements.

Table of contents

ONEOK, Inc. and Subsidiaries    
CONSOLIDATED BALANCE SHEETS    
  December 31, December 31,
  2016 2015
Assets 
(Thousands of dollars)
Current assets    
Cash and cash equivalents $248,875
 $97,619
Accounts receivable, net 872,430
 593,979
Materials and supplies 60,912
 76,696
Natural gas and natural gas liquids in storage 140,034
 128,084
Commodity imbalances 60,896
 38,681
Other current assets 45,986
 39,946
Assets of discontinued operations (Note Q) 551
 205
Total current assets 1,429,684
 975,210
     
Property, plant and equipment  
  
Property, plant and equipment 15,078,497
 14,530,460
Accumulated depreciation and amortization 2,507,094
 2,156,471
Net property, plant and equipment (Note E) 12,571,403
 12,373,989
     
Investments and other assets  
  
Investments in unconsolidated affiliates (Note N) 958,807
 948,221
Goodwill and intangible assets (Note F) 1,005,359
 1,017,258
Other assets 162,998
 112,598
Assets of discontinued operations (Note Q) 10,500
 18,835
Total investments and other assets 2,137,664
 2,096,912
Total assets $16,138,751
 $15,446,111
See accompanying Notes to Consolidated Financial Statements.
Table of contents

ONEOK, Inc. and Subsidiaries    
CONSOLIDATED BALANCE SHEETS    
  December 31, December 31,
  2016 2015
Liabilities and equity 
(Thousands of dollars)
Current liabilities    
Current maturities of long-term debt (Note G) $410,650
 $110,650
Short-term borrowings (Note G) 1,110,277
 546,340
Accounts payable 874,731
 615,982
Commodity imbalances 142,646
 74,460
Accrued interest 112,514
 129,043
Other current liabilities 166,042
 132,556
Liabilities of discontinued operations (Note Q) 19,841
 29,235
Total current liabilities 2,836,701
 1,638,266
     
Long-term debt, excluding current maturities (Note G) 7,919,996
 8,323,582
     
Deferred credits and other liabilities  
  
Deferred income taxes (Note M) 1,623,822
 1,436,715
Other deferred credits 321,846
 264,248
Liabilities of discontinued operations (Note Q) 7,471
 16,964
Total deferred credits and other liabilities 1,953,139
 1,717,927
     
Commitments and contingencies (Note P) 

 

     
Equity (Note H)  
  
ONEOK shareholders’ equity:  
  
Common stock, $0.01 par value:  
  
authorized 600,000,000 shares; issued 245,811,180 shares and outstanding
210,681,661 shares at December 31, 2016; issued 245,811,180 shares and
outstanding 209,731,028 shares at December 31, 2015
 2,458
 2,458
Paid-in capital 1,234,314
 1,378,444
Accumulated other comprehensive loss (Note I) (154,350) (127,242)
Retained earnings 
 
Treasury stock, at cost: 35,129,519 shares at December 31, 2016 and
36,080,152 shares at December 31, 2015
 (893,677) (917,862)
Total ONEOK shareholders’ equity 188,745
 335,798
     
Noncontrolling interests in consolidated subsidiaries 3,240,170
 3,430,538
     
Total equity 3,428,915
 3,766,336
Total liabilities and equity $16,138,751
 $15,446,111
See accompanying Notes to Consolidated Financial Statements.

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Table of contents

ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF CASH FLOWS  
  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars)
Operating activities      
Net income $743,499
 $379,195
 $663,108
Adjustments to reconcile net income to net cash provided by operating activities:      
Depreciation and amortization 391,585
 354,620
 306,038
Impairment charges 
 264,256
 76,412
Equity in net earnings from investments (139,690) (125,300) (117,415)
Distributions received from unconsolidated affiliates 144,673
 122,003
 117,912
Deferred income taxes 211,638
 137,737
 156,728
Share-based compensation expense 40,563
 16,435
 26,226
Pension and postretirement benefit expense, net of contributions 11,643
 14,814
 18,093
Allowance for equity funds used during construction (209) (2,179) (14,937)
Gain on sale of assets (9,635) (5,629) (6,599)
Changes in assets and liabilities, net of acquisitions:  
  
  
Accounts receivable (285,806) 157,051
 381,513
Natural gas and natural gas liquids in storage (11,950) 6,050
 160,860
Accounts payable 287,632
 (205,143) (417,993)
Commodity imbalances, net 45,971
 (4,083) (90,354)
Settlement of exit activities liabilities (19,906) (38,536) (51,757)
Accrued interest (16,529) 24,166
 (4,351)
Risk-management assets and liabilities (78,136) (32,370) 59,539
Other assets and liabilities, net 36,271
 (56,107) 22,587
Cash provided by operating activities 1,351,614
 1,006,980
 1,285,610
Investing activities  
  
  
Capital expenditures (less allowance for equity funds used during construction) (624,634) (1,188,312) (1,779,150)
Cash paid for acquisitions, net of cash received 
 
 (814,934)
Contributions to unconsolidated affiliates (68,275) (27,540) (1,063)
Distributions received from unconsolidated affiliates in excess of cumulative earnings 52,044
 33,915
 21,107
Proceeds from sale of assets 25,420
 3,825
 7,817
Other 
 (12,607) 
Cash used in investing activities (615,445) (1,190,719) (2,566,223)
Financing activities  
  
  
Dividends paid (517,601) (509,197) (443,817)
Distributions to noncontrolling interests (549,419) (535,825) (447,459)
Borrowing (repayment) of short-term borrowings, net 563,937
 (508,956) 490,834
Issuance of ONE Gas debt, net of discounts 
 
 1,199,994
Issuance of long-term debt, net of discounts 1,000,000
 1,291,506
 
ONE Gas long-term debt financing costs 
 
 (9,663)
Debt financing costs (2,770) (17,515) 
Repayment of long-term debt (1,108,040) (7,753) (557,679)
Issuance of common stock 21,971
 20,669
 19,150
Issuance of common units, net of issuance costs 
 375,660
 1,113,139
Cash of ONE Gas at separation 
 
 (60,000)
Other 7,130
 
 
Cash provided by (used in) financing activities (584,792) 108,589
 1,304,499
Change in cash and cash equivalents 151,377
 (75,150) 23,886
Change in cash and cash equivalents included in discontinued operations (121) (43) 3,361
Change in cash and cash equivalents from continuing operations 151,256
 (75,193) 27,247
Cash and cash equivalents at beginning of period 97,619
 172,812
 145,565
Cash and cash equivalents at end of period $248,875
 $97,619
 $172,812
Supplemental cash flow information:  
  
  
Cash paid for interest, net of amounts capitalized $461,208
 $367,835
 $340,144
Cash paid (refunds received) for income taxes $361
 $3,324
 $(11,881)
See accompanying Notes to Consolidated Financial Statements.
Table of contents

ONEOK, Inc. and Subsidiaries        
CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY  
   
  ONEOK Shareholders’ Equity
  
Common
Stock
Issued
 
Common
Stock
 
Paid-in
Capital
 
Accumulated
Other
Comprehensive
Loss
  
(Shares)
 
(Thousands of dollars)
January 1, 2014 245,811,180
 $2,458
 $1,433,600
 $(121,987)
Net income 
 
 
 
Other comprehensive income (loss) 
 
 
 (17,755)
Common stock issued 
 
 (18,307) 
Common stock dividends - $2.125 per share (Note H) 
 
 
 
Issuance of common units of ONEOK Partners (Note O) 
 
 156,143
 
Distribution of ONE Gas to shareholders (Note Q) 
 
 
 3,389
Distributions to noncontrolling interests 
 
 
 
West Texas LPG noncontrolling interest (Note R) 
 
 
 
Other 
 
 (29,853) 
December 31, 2014 245,811,180
 2,458
 1,541,583
 (136,353)
Net income 
 
 
 
Other comprehensive income (loss) (Note I) 
 
 
 9,111
Common stock issued 
 
 (7,550) 
Common stock dividends - $2.43 per share (Note H) 
 
 (126,090) 
Issuance of common units of ONEOK Partners (Note O) 
 
 (34,446) 
Distributions to noncontrolling interests 
 
 
 
Other 
 
 4,947
 
December 31, 2015 245,811,180
 2,458
 1,378,444
 (127,242)
Net income 
 
 
 
Other comprehensive income (loss) (Note I) 
 
 
 (27,108)
Common stock issued 
 
 2,331
 
Common stock dividends - $2.46 per share (Note H) 
 
 (165,562) 
Distributions to noncontrolling interests 
 
 
 
Other 
 
 19,101
 
December 31, 2016 245,811,180
 $2,458
 $1,234,314
 $(154,350)
ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF INCOME      
       
  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars, except per share amounts)
Revenues      
Commodity sales $8,916,047
 $11,395,642
 $9,862,652
Services 1,248,320
 1,197,554
 2,311,255
Total revenues (Note P) 10,164,367
 12,593,196
 12,173,907
Cost of sales and fuel (exclusive of items shown separately below) 6,788,040
 9,422,708
 9,538,045
Operations and maintenance 863,708
 803,146
 724,314
Depreciation and amortization 476,535
 428,557
 406,335
Impairment of long-lived assets (Note D) 
 
 15,970
General taxes 119,156
 103,922
 98,396
(Gain) loss on sale of assets 2,575
 (601) (924)
Operating income 1,914,353
 1,835,464
 1,391,771
Equity in net earnings from investments (Note M) 154,541
 158,383
 159,278
Impairment of equity investments (Note M) 
 
 (4,270)
Allowance for equity funds used during construction 64,815
 7,962
 107
Other income 27,058
 674
 15,385
Other expense (18,003) (14,928) (35,812)
Interest expense (net of capitalized interest of $107,275, $28,062 and $5,510, respectively) (491,773) (469,620) (485,658)
Income before income taxes 1,650,991
 1,517,935
 1,040,801
Income taxes (Note L) (372,414) (362,903) (447,282)
Net income 1,278,577
 1,155,032
 593,519
Less: Net income attributable to noncontrolling interests 
 3,329
 205,678
Net income attributable to ONEOK 1,278,577
 1,151,703
 387,841
Less: Preferred stock dividends 1,100
 1,100
 767
Net income available to common shareholders $1,277,477
 $1,150,603
 $387,074
       
Basic earnings per common share (Note I) $3.09
 $2.80
 $1.30
       
Diluted earnings per common share (Note I) $3.07
 $2.78
 $1.29
Average shares (thousands)
      
Basic 413,560
 411,485
 297,477
Diluted 415,444
 414,195
 299,780
See accompanying Notes to Consolidated Financial Statements.

Table of contents
ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME    
   
  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars)
Net income $1,278,577
 $1,155,032
 $593,519
Other comprehensive income (loss), net of tax  
  
  
Change in fair value of derivatives, net of tax of $44,149, $1,694 and $19,006, respectively (147,803) (5,673) (21,408)
Derivative amounts reclassified to net income, net of tax of $6,058, $(11,013) and $(26,899), respectively (21,057) 36,870
 63,687
Change in retirement and other postretirement benefit plan obligations, net of tax of $2,910, $(1,425) and $(878), respectively (9,696) 4,771
 (4,175)
Other comprehensive income (loss) of unconsolidated affiliates, net of tax of $2,152, $(724) and $145, respectively (7,205) 2,424
 (970)
Total other comprehensive income (loss), net of tax (185,761) 38,392
 37,134
Comprehensive income 1,092,816
 1,193,424
 630,653
Less: Comprehensive income attributable to noncontrolling interests 
 3,329
 236,704
Comprehensive income attributable to ONEOK $1,092,816
 $1,190,095
 $393,949
See accompanying Notes to Consolidated Financial Statements.



ONEOK, Inc. and Subsidiaries        
CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY  
(Continued)        
  ONEOK Shareholders’ Equity    
  
Retained
Earnings
 
Treasury
Stock
 
Noncontrolling
Interest in
Consolidated
Subsidiaries
 
Total
Equity
  
(Thousands of dollars)
January 1, 2014 $2,020,815
 $(997,035) $2,507,329
 $4,845,180
Net income 314,107
 
 349,001
 663,108
Other comprehensive income (loss) 
 
 (22,403) (40,158)
Common stock issued 
 43,334
 
 25,027
Common stock dividends - $2.125 per share (Note H) (443,817) 
 
 (443,817)
Issuance of common units of ONEOK Partners (Note O) 
 
 864,387
 1,020,530
Distribution of ONE Gas to shareholders (Note Q) (1,752,977) 
 
 (1,749,588)
Distributions to noncontrolling interests 
 
 (447,459) (447,459)
West Texas LPG noncontrolling interest (Note R) 
 
 162,913
 162,913
Other 
 
 
 (29,853)
December 31, 2014 138,128

(953,701)
3,413,768

4,005,883
Net income 244,977
 
 134,218
 379,195
Other comprehensive income (loss) (Note I) 
 
 (9,629) (518)
Common stock issued 
 35,839
 
 28,289
Common stock dividends - $2.43 per share (Note H) (383,107) 
 
 (509,197)
Issuance of common units of ONEOK Partners (Note O) 
 
 428,443
 393,997
Distributions to noncontrolling interests 
 
 (535,825) (535,825)
Other 2
 
 (437) 4,512
December 31, 2015 
 (917,862) 3,430,538
 3,766,336
Net income 352,039
 
 391,460
 743,499
Other comprehensive income (loss) (Note I) 
 
 (28,367) (55,475)
Common stock issued 
 24,185
 
 26,516
Common stock dividends - $2.46 per share (Note H) (352,039) 
 
 (517,601)
Distributions to noncontrolling interests 
 
 (549,419) (549,419)
Other 
 
 (4,042) 15,059
December 31, 2016 $
 $(893,677) $3,240,170
 $3,428,915
ONEOK, Inc. and Subsidiaries    
CONSOLIDATED BALANCE SHEETS    
     
  December 31, December 31,
  2019 2018
Assets 
(Thousands of dollars)
Current assets    
Cash and cash equivalents $20,958
 $11,975
Accounts receivable, net 835,121
 818,958
Materials and supplies 201,749
 141,174
Natural gas and NGLs in storage 304,926
 296,667
Commodity imbalances 25,267
 29,050
Other current assets 82,313
 100,808
Total current assets 1,470,334
 1,398,632
Property, plant and equipment 

 

Property, plant and equipment 22,051,492
 18,030,963
Accumulated depreciation and amortization 3,702,807
 3,264,312
Net property, plant and equipment (Note D) 18,348,685
 14,766,651
Investments and other assets 

 

Investments in unconsolidated affiliates (Note M) 861,844
 969,150
Goodwill and intangible assets (Note E) 957,833
 967,142
Other assets 173,425
 130,096
Total investments and other assets 1,993,102
 2,066,388
Total assets $21,812,121
 $18,231,671


Table
ONEOK, Inc. and Subsidiaries    
CONSOLIDATED BALANCE SHEETS    
(Continued)    
  December 31, December 31,
  2019 2018
Liabilities and equity 
(Thousands of dollars)
Current liabilities  
  
Current maturities of long-term debt (Note F) $7,650
 $507,650
Short-term borrowings (Note F) 220,000
 
Accounts payable 1,209,900
 1,116,337
Commodity imbalances 104,480
 110,197
Accrued interest 190,750
 161,377
Finance lease liability (Note O) 1,949
 1,765
Other current liabilities 285,569
 211,110
Total current liabilities 2,020,298
 2,108,436
Long-term debt, excluding current maturities (Note F) 12,479,757
 8,873,334
Deferred credits and other liabilities    
Deferred income taxes (Note L) 536,063
 219,731
Finance lease liability (Note O) 24,296
 26,244
Other deferred credits 525,756
 424,383
Total deferred credits and other liabilities 1,086,115
 670,358
Commitments and contingencies (Note N)    
Equity (Note G)    
ONEOK shareholders’ equity:    
Preferred stock, $0.01 par value:
authorized and issued 20,000 shares at December 31, 2019, and at December 31, 2018
 
 
Common stock, $0.01 par value:
authorized 1,200,000,000 shares; issued 445,016,234 shares and outstanding
413,239,050 shares at December 31, 2019; issued 445,016,234 shares and outstanding 411,532,606 shares at December 31, 2018
 4,450
 4,450
Paid-in capital 7,403,895
 7,615,138
Accumulated other comprehensive loss (Note H) (374,000) (188,239)
Retained earnings 
 
Treasury stock, at cost: 31,777,184 shares at December 31, 2019, and 33,483,628 shares at December 31, 2018 (808,394) (851,806)
Total equity 6,225,951
 6,579,543
Total liabilities and equity $21,812,121
 $18,231,671
See accompanying Notes to Consolidated Financial Statements.



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ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF CASH FLOWS    
  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars)
Operating activities      
Net income $1,278,577
 $1,155,032
 $593,519
Adjustments to reconcile net income to net cash provided by operating activities:      
Depreciation and amortization 476,535
 428,557
 406,335
Impairment charges 
 
 20,240
Noncash contribution of preferred stock, net of tax 
 
 12,600
Equity in net earnings from investments (154,541) (158,383) (159,278)
Distributions received from unconsolidated affiliates 163,476
 170,528
 167,372
Deferred income taxes 372,729
 361,010
 437,917
Share-based compensation expense 37,147
 31,664
 26,262
Allowance for equity funds used during construction (64,815) (7,962) (107)
Other, net 1,567
 (132) 3,155
Changes in assets and liabilities:    
  
Accounts receivable (19,688) 383,993
 (330,521)
Natural gas and NGLs in storage (8,259) 38,456
 (202,259)
Accounts payable (62,946) (320,132) 261,305
Commodity imbalances, net (1,934) (44,302) 43,699
Accrued interest 29,373
 26,068
 22,795
Risk-management assets and liabilities (86,268) 117,717
 37,617
Other assets and liabilities, net (14,174) 4,605
 (25,239)
Cash provided by operating activities 1,946,779
 2,186,719
 1,315,412
Investing activities  
  
  
Capital expenditures (less allowance for equity funds used during construction) (3,848,349) (2,141,475) (512,393)
Contributions to unconsolidated affiliates (4,028) (1,748) (87,861)
Distributions received from unconsolidated affiliates in excess of cumulative earnings 94,168
 26,757
 28,742
Other, net (10,549) 1,578
 3,879
Cash used in investing activities (3,768,758) (2,114,888) (567,633)
Financing activities  
  
  
Dividends paid (1,457,628) (1,335,058) (829,414)
Distributions to noncontrolling interests 
 (3,500) (276,260)
Borrowing (repayment) of short-term borrowings, net 220,000
 (614,673) (495,604)
Issuance of long-term debt, net of discounts 4,185,435
 1,795,773
 1,190,496
Debt financing costs (29,747) (13,441) (11,425)
Repayment of long-term debt (1,057,348) (932,650) (994,776)
Issuance of common stock 29,040
 1,203,981
 471,358
Acquisition of noncontrolling interests 
 (195,000) 
Other, net (58,790) (2,481) (13,836)
Cash provided by (used in) financing activities 1,830,962
 (97,049) (959,461)
Change in cash and cash equivalents 8,983
 (25,218) (211,682)
Cash and cash equivalents at beginning of period 11,975
 37,193
 248,875
Cash and cash equivalents at end of period $20,958
 $11,975
 $37,193
Supplemental cash flow information:  
  
  
Cash paid for interest, net of amounts capitalized $435,165
 $418,244
 $432,210
Cash paid for income taxes, net of refunds $2,690
 $2,225
 $6,633
See accompanying Notes to Consolidated Financial Statements.

ONEOK, Inc. and Subsidiaries        
CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY    
   
  ONEOK Shareholders’ Equity
  
Common
Stock Issued
 Preferred Stock Issued 
Common
Stock
 Preferred Stock 
Paid-in
Capital
  
(Shares)
 
(Thousands of dollars)
January 1, 2017 245,811,180
 
 $2,458
 $
 $1,234,314
Cumulative effect adjustment for adoption of ASU 2016-09 (a) 
 
 
 
 
Net income 
 
 
 
 
Other comprehensive income (loss) 
 
 
 
 
Preferred stock issued 
 20,000
 
 
 20,000
Preferred stock dividends - $38.35 per share (Note G) 
   
 
 (767)
Common stock issued 8,434,223
 
 85
 
 456,537
Common stock dividends - $2.72 per share (Note G) 
 
 
 
 (367,578)
Distributions to noncontrolling interests 
 
 
 
 
Acquisition of noncontrolling interests (Note G) 168,920,831
 
 1,689
 
 5,228,580
Other, net 
 
 
 
 17,792
December 31, 2017 423,166,234
 20,000
 4,232
 
 6,588,878
Cumulative effect adjustment for adoption of ASUs (b) 
 
 
 
 
Net income 
 
 
 
 
Other comprehensive income (loss) (Note H) 
 
 
 
 
Preferred stock dividends - $55.00 per share (Note G) 
 
 
 
 
Common stock issued 21,850,000
 
 218
 
 1,183,321
Common stock dividends - $3.245 per share (Note G) 
 
 
 
 (144,805)
Distributions to noncontrolling interests 
 
 
 
 
Contributions from noncontrolling interests 
 
 
 
 
Acquisition of noncontrolling interests (Note G) 
 
 
 
 (21,220)
Other, net 
 
 
 
 8,964
December 31, 2018 445,016,234
 20,000
 4,450
 
 7,615,138
Cumulative effect adjustment for adoption of ASU 2016-02 (Note A) 
 
 
 
 
Net income 
 
 
 
 
Other comprehensive income (loss) (Note H) 
 
 
 
 
Preferred stock dividends - $55.00 per share (Note G) 
 
 
 
 
Common stock issued 
 
 
 
 (7,667)
Common stock dividends - $3.53 per share (Note G) 
 
 
 
 (180,421)
Other, net 
 
 
 
 (23,155)
December 31, 2019 445,016,234
 20,000
 $4,450
 $
 $7,403,895


ONEOK, Inc. and Subsidiaries      
CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY    
(Continued)          
  ONEOK Shareholders’ Equity    
  Accumulated
Other
Comprehensive
Loss
 
Retained
Earnings
 
Treasury
Stock
 
Noncontrolling
Interests in
Consolidated
Subsidiaries
 
Total
Equity
  
(Thousands of dollars)
January 1, 2017 $(154,350) $
 $(893,677) $3,240,170
 $3,428,915
Cumulative effect adjustment for adoption of ASU 2016-09 (a) 
 73,368
 
 
 73,368
Net income 
 387,841
 
 205,678
 593,519
Other comprehensive income (loss) 6,108
 
 
 31,026
 37,134
Preferred stock issued 
 
 
 
 20,000
Preferred stock dividends - $38.35 per share (Note G) 
 
 
 
 (767)
Common stock issued 
 
 16,964
 
 473,586
Common stock dividends - $2.72 per share (Note G) 
 (461,209) 
 
 (828,787)
Distributions to noncontrolling interests 
 
 
 (276,260) (276,260)
Acquisition of noncontrolling interests (Note G) (40,288) 
 
 (3,043,519) 2,146,462
Other, net 
 
 
 390
 18,182
December 31, 2017 (188,530) 
 (876,713) 157,485
 5,685,352
Cumulative effect adjustment for adoption of ASUs (b) (38,101) 39,803
 
 17
 1,719
Net income 
 1,151,703
 
 3,329
 1,155,032
Other comprehensive income (loss) (Note H) 38,392
 
 
 
 38,392
Preferred stock dividends - $55.00 per share (Note G) 
 (1,100) 
 
 (1,100)
Common stock issued 
 
 24,907
 
 1,208,446
Common stock dividends - $3.245 per share (Note G) 
 (1,190,406) 
 
 (1,335,211)
Distributions to noncontrolling interests 
 
 
 (3,500) (3,500)
Contributions from noncontrolling interests 
 
 
 16,449
 16,449
Acquisition of noncontrolling interests (Note G) 
 
 
 (173,780) (195,000)
Other, net 
 
 
 
 8,964
December 31, 2018 (188,239) 
 (851,806) 
 6,579,543
Cumulative effect adjustment for adoption of ASU 2016-02 (Note A) 
 (67) 
 
 (67)
Net income 
 1,278,577
 
 
 1,278,577
Other comprehensive income (loss) (Note H) (185,761) 
 
 
 (185,761)
Preferred stock dividends - $55.00 per share (Note G) 
 (1,100) 
 
 (1,100)
Common stock issued 
 
 43,412
 
 35,745
Common stock dividends - $3.53 per share (Note G) 
 (1,277,410) 
 
 (1,457,831)
Other, net 
 
 
 
 (23,155)
December 31, 2019 $(374,000) $
 $(808,394) $
 $6,225,951
(a) - Includes adjustment increasing beginning retained earnings in the first quarter 2017 of contents$73.4 million to recognize previously unrecognized cumulative excess tax benefits related to share-based payments on a modified retrospective basis.
(b) - Includes cumulative effect for adoption of the following: ASU 2014-09, “Revenue from Contracts with Customers (Topic 606)”; ASU 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities”; and ASU 2018-02, “Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.”

See accompanying Notes to Consolidated Financial Statements.


ONEOK, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS


A.SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES


Organization and Nature of Operations- We are the sole general partner and owned 41.2 percent of ONEOK Partners, L.P. (NYSE: OKS), one of the largest publicly traded master limited partnerships, at December 31, 2016. We are a corporation incorporated under the laws of the state of Oklahoma, and our common stock is listed on the NYSE under the trading symbol “OKE.”Oklahoma.


On January 31, 2017, we and ONEOK Partners entered into the Merger Agreement, by and among ONEOK, Merger Sub, ONEOK Partners and ONEOK Partners GP, the general partner of ONEOK Partners, pursuant to which we will acquire all of the outstanding common units representing limited partner interests in ONEOK Partners not already directly or indirectly owned by us. Upon the terms and conditions set forth in the Merger Agreement, Merger Sub will be merged with and into ONEOK Partners, with ONEOK Partners continuing as a wholly owned subsidiary of ours, in a taxable transaction to ONEOK Partners’ unitholders. For additional information on this transaction, see Note B.

ONEOK Partners is a publicly traded master limited partnership involved in the gathering, processing, storage and transportation of natural gas in the United States. In addition, ONEOK Partners owns one of the nation’s premier natural gas liquids systems, connecting NGL supply in the Mid-Continent, Permian and Rocky Mountain regions with key market centers.

TheOur Natural Gas Gathering and Processing segment gathersprovides midstream services to producers in North Dakota, Montana, Wyoming, Kansas and processesOklahoma. Raw natural gas inis typically gathered at the Mid-Continent region, which includes the NGL-rich STACKwellhead, compressed and SCOOP areas in the Anadarko Basin and the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations of Oklahoma and Kansas, and the Hugoton and Central Kansas Uplift Basins in Kansas. ONEOK Partners also gathers and/or processestransported through pipelines to our processing facilities. Processed natural gas, in two producing basins inusually referred to as residue natural gas, is then recompressed and delivered to natural gas pipelines, storage facilities and end users. The NGLs separated from the Rocky Mountain region: the Williston Basin, which spans portions of North Dakota and Montana and includes the oil-producing, NGL-rich Bakken Shale and Three Forks formations; and the Powder River Basin located in Wyoming, which includes the NGL-rich Niobrara Shale and Frontier, Turner and Sussex formations in Wyoming.raw natural gas are delivered through NGL pipelines to fractionation facilities for further processing.


TheOur Natural Gas Liquids segment consists ofowns and operates facilities that gather, fractionate, treat and treatdistribute NGLs and store NGL products, primarily in Oklahoma, Kansas, Texas, New Mexico and the Rocky Mountain region, where it provideswhich includes the Williston, Powder River and DJ Basins. We provide midstream services to producers of NGLs.NGLs and deliver those products to the two primary market centers, one in the Mid-Continent in Conway, Kansas, and the other in the Gulf Coast in Mont Belvieu, Texas. The Natural Gas Liquids segment ownsmajority of the pipeline-connected natural gas processing plants in the Williston Basin, Oklahoma, Kansas and the Texas Panhandle are connected to our NGL gathering systems. We own or hashave an ownership interest in FERC-regulated natural gas liquidsNGL gathering and distribution pipelines in Oklahoma, Kansas, Texas, New Mexico, Montana, North Dakota, Wyoming and Colorado, and terminal and storage facilities in Missouri, Nebraska, Iowa and Illinois. ItWe also ownsown FERC-regulated natural gas liquidsNGL distribution and refined petroleum products pipelines in Kansas, Missouri, Nebraska, Iowa, Illinois and Indiana that connect itsour Mid-Continent assets with Midwest markets, including Chicago, Illinois. ONEOK Partners’ Natural Gas Liquids segment owns and operates truck- and rail-loading and -unloading facilities that interconnect with its NGL fractionation and pipeline assets.


TheOur Natural Gas Pipelines segment operatesprovides interstate and intrastate natural gas transmissiontransportation and storage services to end users through its wholly owned assets and its 50% ownership interests in Northern Border Pipeline and Roadrunner. Our interstate pipelines are regulated by the FERC and natural gas storage facilities. ONEOK Partners’ FERC-regulated interstate natural gas pipeline assets transport natural gas through pipelinesare located in North Dakota, Minnesota, Wisconsin, Illinois, Indiana, Kentucky, Tennessee, Oklahoma, Texas and New Mexico. ONEOK Partners’Our intrastate natural gas pipeline and storage assets are located in Oklahoma, transport natural gas throughout the stateKansas and have access to theTexas. Our assets connect major natural gas producing areas in the Mid-Continent region, which include the emerging STACKbasins and SCOOP areas in the Anadarko Basin and the Cana-Woodford Shale, Woodford Shale, Springer Shale, Meramec, Granite Wash and Mississippian Lime formations. The Roadrunner pipeline transports natural gas from the Permian Basin in West Texas to the Mexican border near El Paso, Texas, and is fully subscribedmarket hubs with 25-year firm demand charge, fee-based agreements. ONEOK Partners owns underground natural gas storage facilities in Oklahoma and Texas that are connected to its intrastate natural gas pipeline assets. ONEOK Partners also has underground natural gas storage facilities in Kansas.end-use customers.


On January 31, 2014, we completed the separation of our former natural gas distribution business into a stand-alone publicly traded company, ONE Gas. In addition, we completed the wind down of our former energy services business on March 31, 2014. Following the separation of the natural gas distribution business and the wind down of our energy services business, our primary source of income and cash flows is generated from our investment in ONEOK Partners. See Note Q for additional discussion of the separation of the natural gas distribution business and the wind down of the energy services business.

For all periods presented, the accompanying consolidated financial statements and notes reflect the results of operations and financial position of our former natural gas distribution and energy services businesses as discontinued operations. Unless indicated otherwise, the information in the Notes to theConsolidation -Our Consolidated Financial Statements relates to our continuing operations.
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Consolidation - Our consolidated financial statements include our accounts and the accounts of our subsidiaries over which we have control or are the primary beneficiary. Management’s judgment is required when:
determining whether an entity is a variable interest entity (VIE);
determining whether we are the primary beneficiary of a VIE; and
identifying events that require reconsideration of whether an entity is a VIE.

As a result of adopting ASU 2015-02 described below, we have concluded that ONEOK Partners is a VIE and that we are the primary beneficiary. Therefore, we continue to consolidate ONEOK Partners. We have recorded noncontrolling interests in consolidated subsidiaries on our Consolidated Balance Sheets to recognize the portion of ONEOK Partners that we do not own. We reflected our ownership interest in ONEOK Partners’ accumulated other comprehensive income (loss) in our consolidated accumulated other comprehensive income (loss). The remaining portion is reflected as an adjustment to noncontrolling interests in consolidated subsidiaries.

ONEOK Partners provides natural gas sales and transportation and storage services to our former natural gas distribution business. Prior to the completion of the energy services wind down, ONEOK Partners provided natural gas sales and transportation and storage services to our former energy services business. While these transactions were eliminated in consolidation in previous periods, they are reflected now as affiliate transactions and not eliminated in consolidation for all periods presented as these transactions have continued with third parties. See Note Q for additional information.

All significant intercompany balances and transactions have been eliminated in consolidation.


Investments in unconsolidated affiliates are accounted for using the equity method if we have the ability to exercise significant influence over operating and financial policies of our investee. Under this method, an investment is carried at its acquisition cost and adjusted each period for contributions made, distributions received and our share of the investee’s comprehensive income. For the investments we account for under the equity method, the premium or excess cost over underlying fair value of net assets is referred to as equity-method goodwill. Impairment of equity investments is recorded when the impairments are other than temporary. These amounts are recorded as investments in unconsolidated affiliates on our accompanying Consolidated Balance Sheets. See Note NM for disclosures of our unconsolidated affiliates.


Distributions paid to us from our unconsolidated affiliates are classified as operating activities on our Consolidated Statements of Cash Flows until the cumulative distributions exceed our proportionate share of income from the unconsolidated affiliate since the date of our initial investment. The amount of cumulative distributions paid to us that exceeds our cumulative proportionate share of income in each period represents a return of investment and is classified as an investing activity on our Consolidated Statements of Cash Flows.


Use of Estimates - The preparation of our consolidated financial statementsConsolidated Financial Statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amount of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements. These estimates and assumptions also affect the reported amounts of revenue and expenses during the reporting period.on our Consolidated Financial Statements. Items that may be estimated include, but are not limited to, the economic useful life of assets, fair value of assets, liabilities and equity-method investments, obligations under employee benefit plans, provisions for uncollectible accounts receivable, unbilled revenues and cost of goods sold, expenses for services received but for which no invoice has been received, provision for income taxes, including any deferred tax valuation allowances, the results of litigation and various other recorded or disclosed amounts. In addition, a portion of our revenues and cost of sales and fuel are recorded based on current month prices and estimated volumes. The estimates are reversed in the following month and recorded with actual volumes and prices.


We evaluate theseour estimates on an ongoing basis using historical experience, consultation with experts and other methods we consider reasonable based on the particular circumstances. Nevertheless, actual results may differ significantly from the estimates. Any effects on our financial position or results of operations from revisions to these estimates are recorded in the period when the facts that give rise to the revision become known.


Fair Value Measurements-We define For our fair value asmeasurements, we utilize market prices, third-party pricing services, present value methods and standard option valuation models to determine the price thatwe would be receivedreceive from the sale of an asset or the transfer of a liability in an orderly transaction between market participants at the measurement date. We use market and income approaches to determine the fair value of our assets and liabilities and consider the markets in which the transactions are executed. We measure the fair value of a group of financial assets and liabilities consistent with how a market participant would price the net risk exposure at the measurement date.


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While manyMany of the contracts in our derivative portfolio are executed in liquid markets where price transparency exists, some contractsexists. Our financial commodity derivatives are executed in markets for which market prices may exist, but the market may be relatively inactive. This results in limited price transparency that requires management’s judgment and assumptions to estimate fair values. For certain transactions, we utilize modeling techniques using NYMEX-settled pricing data and implied forward LIBOR curves. Inputs into our fair value estimates include commodity-exchange prices, over-the-counter quotes, historical correlations of pricing data, data obtained from third-party pricing services and LIBOR and other liquid money-market instrument rates.generally settled through a NYMEX or Intercontinental Exchange (ICE) clearing broker account with daily margin requirements. We validate our valuation inputs with third-party information and settlement prices from other sources, where available.


In addition, as prescribed by the income approach, weWe compute the fair value of theour derivative portfolio by discounting the projected future cash flows from theour derivative assets and liabilities to present value using interest-rate yields to calculate present-value discount factors derived from the implied forward LIBOR Eurodollar futures and the LIBOR interest-rate swaps market. We also take into consideration the potential impact on market prices of liquidating positions in an orderly manner over a reasonable period of time under current market conditions. We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using specific and sector bond yields and monitoring the credit default swap markets. Although we use our best estimates to determine theyield curve. The fair value of the executed derivative contracts, the ultimate market prices realized could differ from our estimates, and the differences could be material.

The fair value of forward-starting interest-rate swaps are determined using financial models that incorporate the implied forward LIBOR yield curve for the same period as the future interest-rate swap settlements. We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using counterparty-specific bond yields. Although we use our best estimates to determine the fair value of the derivative contracts we have executed, the ultimate market prices realized could differ materially from our estimates.


Fair Value Hierarchy - At each balance sheet date, we utilize a fair value hierarchy to classify fair value amounts recognized or disclosed in our financial statements based on the observability of inputs used to estimate such fair value. The levels of the hierarchy are described below:
Level 1 - fair value measurements are based on unadjusted quoted prices for identical securities in active markets, including NYMEX-settled prices.markets. These balances are comprisedcomposed predominantly of exchange-traded derivative contracts for natural gas and crude oil.
Level 2 - fair value measurements are based on significant observable pricing inputs, such as NYMEX-settledincluding quoted prices for natural gassimilar assets and crude oil,liabilities in active markets and financial models that utilize implied forward LIBOR yield curves forinputs from third-party pricing services supported with corroborative evidence. These balances are composed of over-the-counter interest-rate swaps.derivatives.
Level 3 - fair value measurements are based on inputs that may include one or more unobservable inputs, including internally developed natural gas basis and NGLcommodity price curves that incorporate observable and unobservable market data from broker quotes and third-party pricing services. These balances are composed predominantly of exchange-cleared and over-the-counter derivatives to hedge NGL price risk and natural gas basis risk between various transaction locations and the NYMEX Henry Hub. Our commodity derivatives are generally valued using forward quotes provided by third-party pricing services that are validated with other market volatilities derived from the most recent NYMEX close spot prices and forward LIBOR curves, and adjustments for the credit risk ofdata. We believe any measurement uncertainty at December 31, 2019, is immaterial as our counterparties. We corroborate the data on which ourLevel 3 fair value estimatesmeasurements are based using our market knowledge of recent transactions, analysis of historical correlationson unadjusted pricing information from broker quotes and validation with independent broker quotes. These balances categorized as Level 3 are comprised of derivatives for natural gas and NGLs.third-party pricing services. We do not believe that our Level 3 fair value estimates have a material impact on our results of operations, as the majority of our derivatives are accounted for as hedges for which ineffectiveness has not been material.hedges.


Determining the appropriate classification of our fair value measurements within the fair value hierarchy requires management’s judgment regarding the degree to which market data is observable or corroborated by observable market data. We categorize derivatives for which fair value is determined using multiple inputs within a single level, based on the lowest level input that is significant to the fair value measurement in its entirety.


See Note CB for discussion of our fair value measurements.measurements disclosures.


Cash and Cash Equivalents - Cash equivalents consist of highly liquid investments, which are readily convertible into cash and have original maturities of three months or less.

Revenue Recognition -Revenues are recognized when control of the promised goods or services is transferred to our customers in an amount that reflects the consideration we expect to be entitled to receive in exchange for those goods or services. Our payment terms vary by customer and contract type, including requiring payment before products or services are delivered to certain customers. However, the term between customer prepayments, completion of our performance obligations, invoicing and receipt of payment due is not significant.


Revenue Recognition - Our reportable segments recognize revenue when services are rendered or product is delivered. TheA significant portion of supply volumes in our Natural Gas Gathering and Processing segment records revenues when natural gas is gathered or processed through ONEOK Partners’ facilities. Theand Natural Gas Liquids segment records revenues basedsegments are under contracts that include the purchase of commodities. Therefore, upon contractedadoption of Topic 606, the contractual fees we charge on these contracts are considered a reduction of the commodity purchase price in cost of sales and fuel. In 2017 and prior periods, we recorded these fees as services revenue. See “Cost of Sales and volumes exchanged or stored under service agreementsFuel” below for a description of these arrangements.

Performance Obligations and Revenue Sources - Revenues sources are disaggregated in the period servicesNote Q and are provided. A portion of revenues for the Natural Gas Pipelines segment and the Natural Gas Liquids segment are recognized based upon contracted capacity and contracted volumes transported and stored under service agreements in the period services are provided. We disaggregate revenue on the Consolidated Statements of Income as follows:
Commodity sales - Commodity sales represent the sale of NGLs, condensate and residue natural gas. ONEOK Partners generally purchases a supplier’s raw natural gas or unfractionated NGLs, which it processes into marketable
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commodities and condensate, then sells those commodities and condensate to downstream customers. Commodity sales are recognized upon delivery or title transfer to the customer, when revenue recognition criteria are met.
Service revenue - Service revenue represents the fees generatedderived from the performance of ONEOK Partners’ services.

ONEOK Partners enters into a variety of contract types that provide commodity sales and service revenue. ONEOK Partners provides services primarily underrevenues, as described below:

Commodity Sales(all segments) - We contract to deliver residue natural gas, condensate, unfractionated NGLs and/or NGL products to customers at a specified delivery point. Our sales agreements may be daily or longer-term contracts for a specified volume. We consider the following typessale and delivery of contracts:
Fee-based - Under fee-based arrangements, ONEOK Partners receiveseach unit of a fee or fees for one or morecommodity an individual performance obligation as the customer is expected to control, accept and benefit from each unit individually. We record revenue when the commodity is delivered tothe customer as this represents the point in time when control of the following services: gathering, compression, processing, transmission and storage of natural gas; and gathering, transportation, fractionation and storage of NGLs. The revenue ONEOK Partners earns from these arrangements generallyproduct is directly relatedtransferred to the volume of natural gas and NGLs that flow through ONEOK Partners’ systems and facilities, andcustomer. Revenue is not normally directly dependent on commodity prices. However, to the extent a sustained decline in commodity prices results in a decline in volumes, ONEOK Partners’ revenues from these arrangements would be reduced. In addition, many of ONEOK Partners’ arrangements provide for fixed fee, minimum volume or firm demand charges. Fee-based arrangements are reported as service revenuerecorded based on the Consolidated Statements of Income.
contracted selling price, which is generally index-based and settled monthly.

Percent-of-proceeds - Under POP arrangements in the Services
Gathering only contracts (Natural Gas Gathering and Processing segment ONEOK Partners generally purchases the producer’s) - Under this type of contract, we charge fees for providing midstream services, which include gathering and treating our customer’s natural gas. Our performance obligation begins with delivery of raw natural gas which it processes intoto our system. This service is treated as one performance obligation that is satisfied over time. We use the output method based on delivery of product to our system as the measure of progress, as our services are performed simultaneously.

POP with fee contracts with producer take-in-kind rights (Natural Gas Gathering and Processing segment) - Under this type of contract, we do not control the stream of unprocessed natural gas andthat we receive at the wellhead due to the producer’s take-in-kind rights. We purchase a portion of the raw natural gas liquids, then sellsstream, charge fees for providing midstream services, which include gathering, treating, compressing and processing our customer’s natural gas. After performing these services, we return primarily the residue natural gas to the producer, sell the remaining commodities and condensate to downstream customers. ONEOK Partners remitsremit a portion of the commodity sales proceeds to the producer accordingless our contractual fees. Our performance obligation begins with delivery of raw natural gas to our system. This service is treated as one performance obligation that is satisfied over time. We use the contractual termsoutput method based on delivery of product to our system as the measure of progress, as our services are performed simultaneously.

Transportation and retains its portion. Typically, ONEOK Partners’ POP arrangements alsoexchange contracts (Natural Gas Liquids segment) - Under this type of contract, we charge fees for providing midstream services, which may include a fee-based component.
bundled combination of gathering, transporting and/or fractionation of our customer’s NGLs. Our performance obligation begins with delivery of unfractionated NGLs or NGL products to our system. These services represent a series of distinct services that are treated as one performance obligation that is satisfied over time. We use the output method based on delivery of product to our system as the measure of progress, as our services are performed simultaneously. For transportation services under a tariff on our NGL transportation pipelines, fees are recorded upon redelivery to our customer at the completion of the transportation services.


In many cases, the Storage contracts (Natural Gas GatheringLiquids and Processing segment providesNatural Gas Pipelines segments) - We reserve a stated storage capacity and inject/withdraw/store commodities for our customer. The capacity reservation and injection/withdrawal/storage services underare considered a bundled service, as we integrate them into one stand-ready obligation provided on a daily basis over the life of the agreement and satisfied over time. Fixed capacity reservation fees are allocated and evenly recognized in revenue. Capacity reservation fees that vary based on a stated or implied economic index and correspond with the costs to provide our services are recognized in revenue as invoiced to our customers. For contracts that containdo not include a combination of the arrangements described above. Whencapacity reservation, transportation, injection and withdrawal fees are recognized in revenue as those services are provided (in addition to raw natural gas purchased) under POP with fee contracts, ONEOK Partners records such fees as service revenueand are dependent on the Consolidated Statementsvolume transported, injected or withdrawn by our customer, which is at our customer’s discretion. We use the output method based on the passage of Income.time to measure satisfaction of the performance obligation associated with our daily stand-ready services.

Firm service transportation contracts (Natural Gas Pipelines segment) - We reserve a stated transportation capacity and transport commodities for our customer. The termscapacity reservation and transportation services are considered a bundled service, as we integrate them into one stand-ready obligation provided on a daily basis over the life of ONEOK Partners’ contractsthe agreement and satisfied over time. Fixed capacity reservation fees are allocated and evenly recognized in revenue. Capacity reservation fees that vary based on natural gas quality conditions,a stated or implied economic index and correspond with the competitive environment whencosts to provide our services are recognized in revenue based on a daily effective fee rate. If the contractscapacity reservation fees vary solely as a contract feature, contract assets or liabilities are signedrecorded for the difference between the amount recorded in revenue and the amount billed to the customer. Transportation fees are recognized in revenue as those services are provided and are dependent on the volume transported by our customer, requirements.which

is at our customer’s discretion. We use the output method based on the passage of time to measure satisfaction of the performance obligation associated with our daily stand-ready services.

Interruptible transportation contracts (Natural Gas Pipelines segment) - We agree to transport natural gas on our pipelines between the customer’s specified nomination and delivery points if capacity is available after satisfying firm transportation service obligations. The transaction price is based on the transportation fees times the volumes transported. These fees may change over time based on an index or other factors provided in the agreement. We use the output method based on delivery of product to the customer to measure satisfaction of the performance obligation. The total consideration for delivered volumes is recorded in revenue at the time of delivery, when the customer obtains control.

See Note P for our revenue disclosures.

Contract Assets and Contract Liabilities - Contract assets and contract liabilities are recorded when the amount of revenue recognized from a contract with a customer differs from the amount billed to the customer and recorded in accounts receivable. Our contract asset balances at the beginning and end of the period primarily relate to our firm service transportation contracts with tiered rates. Our contract liabilities primarily represent deferred revenue on contributions in aid of construction received from customers for which revenue is recognized over the contract periods, which range from 5 to 10 years, and deferred revenue on NGL storage contracts for which revenue is recognized over a one-year term.

Cost of Sales and Fuel - Cost of sales and fuel primarily includes (i) the cost of purchased commodities, including NGLs, natural gas and condensate, (ii) fees incurred for third-party transportation, fractionation and storage of commodities, and (iii) fuel and power costs incurred to operate ONEOK Partners’our own facilities that gather, process, transport and store commodities.commodities, and (iv) an offset from the contractual fees deducted from the cost of purchased commodities under the contract types below:


POP with fee contracts with no producer take-in-kind rights (Natural Gas Gathering and Processing segment) - We purchase raw natural gas and charge contractual fees for providing midstream services, which include gathering, treating, compressing and processing the producer’s natural gas. After performing these services, we sell the commodities and return a portion of the commodity sales proceeds to the producer less our contractual fees.

Purchase with fee (Natural Gas Liquids segment) - Under this type of contract, we purchase raw, unfractionated NGLs at an index price and charge fees for providing midstream services, which may include a bundled combination of gathering, transporting and/or fractionation of our customer’s NGLs.

Operations and Maintenance - Operations and maintenance primarily includes (i) payroll and benefit costs, (ii) third-party costs for operations, maintenance and integrity management, regulatory compliance and environmental and safety, and (iii) other business related service costs.


Accounts Receivable - Accounts receivable represent valid claims against nonaffiliated customers for products sold or services rendered, net of allowances for doubtful accounts. We assess the creditworthiness of our counterparties on an ongoing basis and require security, including prepayments and other forms of collateral, when appropriate. Outstanding customer receivables are reviewed regularly for possible nonpayment indicators, and allowances for doubtful accounts are recorded based upon management’s estimate of collectability at each balance sheet date. At December 31, 20162019 and 20152018, theour allowance for doubtful accounts was not material.


InventoryUpdate - Upon adoption of ASU 2016-13 in January 2020, we are required to present accounts receivable net of an allowance for credit losses to reflect the net amount expected to be collected. This assessment is based on historical information, current conditions and supportable forecasts. See “Recently Issued Accounting Standards Update” table below for more information.

Inventory -The values of current natural gas and NGLs in storage are determined using the lower of weighted-average cost or market method.net realizable value. Noncurrent natural gas and NGLs are classified as property and valued at cost. Materials and supplies are valued at average cost.


Commodity Imbalances -Commodity imbalances represent amounts payable or receivable for NGL exchange contracts and natural gas pipeline imbalances and are valued at market prices. Under the majority of ONEOK Partners’our NGL exchange agreements, itwe physically receivesreceive volumes of unfractionated NGLs, including the risk of loss and legal title to such volumes, from the exchange counterparty. In turn, ONEOK Partners deliverswe deliver NGL products back to the customer and chargescharge them gathering, fractionationtransportation and transportationfractionation fees. To the extent that the volumes ONEOK Partners receiveswe receive under such agreements differ from those it delivers,we deliver, we record a net exchange receivable or payable position with the counterparties. These net exchange receivables and payables are generally

settled with movements of NGL products rather than with cash. Natural gas pipeline imbalances are settled in cash or in-kind, subject to the terms of the pipelines’ tariffs or by agreement.


Derivatives and Risk Management-We utilize derivatives to reduce our market-risk exposure to commodity price and interest-rate fluctuations and to achieve more predictable cash flows. We record all derivative instruments at fair value, with the exception of normal purchases and normal sales transactions that are expected to result in physical delivery. Commodity price and interest-rate volatility may have a significant impact on the fair value of derivative instruments as of a given date.
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The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and, if so, the reason for holding it. The table below summarizes the various ways in which we account for our derivative instruments and the impact on our consolidated financial statements:Consolidated Financial Statements:
  Recognition and Measurement
Accounting TreatmentBalance Sheet Income Statement
Normal purchases and
normal sales
-Fair value not recorded-Change in fair value not recognized in earnings
Mark-to-market-Recorded at fair value-Change in fair value recognized in earnings
Cash flow hedge-Recorded at fair value-
Ineffective portion of the gain or loss on the
derivative instrument is recognized in earnings
-
Effective portion of theThe gain or loss on the
derivative instrument is reported initially as a
component of accumulated other
comprehensive income (loss)
-
Effective portion of theThe gain or loss on the
derivative instrument is reclassified out of
accumulated other comprehensive income (loss)
into earnings when the forecasted transaction
affects earnings
Fair value hedge-Recorded at fair value-
The gain or loss on the derivative instrument is
recognized in earnings
 -
Change in fair value of the hedged item is
recorded as an adjustment to book value
-
Change in fair value of the hedged item is
recognized in earnings


To reduce our exposure to fluctuations in natural gas, NGLs and condensate prices, we periodically enter into futures, forward purchases and sales, options or swap transactions in order to hedge anticipated purchases and sales of natural gas, NGLs and condensate. Interest-rate swaps are used from time to time to manage interest-rate risk. Under certain conditions, thesewe designate our derivative instruments are designated as a hedge of exposure to changes in fair values or cash flows. AllWe formally document all relationships between hedging instruments and hedged items, are formally documented, as well as risk-management objectives and strategies for undertaking various hedge transactions, and methods for assessing and testing correlation and hedge ineffectiveness. Theeffectiveness. We specifically identify the forecasted transaction that has been designated as the hedged item in a cash flow hedge relationship is specifically identified. Therelationship. We assess the effectiveness of hedging relationships are assessed quarterlyat inception of the hedge by performing an effectiveness analysis on theour fair value and cash flow hedging relationships to determine whether the hedge relationships are highly effective on a retrospective and prospective basis. Normaleffective. Subsequently we perform qualitative assessments. We also document our normal purchases and normal sales transactions that are expectedwe expect to result in physical delivery and through election, arethat we elect to exempt from derivative accounting treatment are also documented.treatment.


The realized revenues and purchase costs of our derivative instruments not considered held for trading purposes and derivatives that qualify as normal purchases or normal sales that are expected to result in physical delivery are reported on a gross basis.


Cash flows from futures, forwards, options and swaps that are accounted for as hedges are included in the same category as the cash flows from the related hedged items in our Consolidated Statements of Cash Flows.


See Notes B and C and D for more discussiondisclosures of our fair value measurements and risk-management and hedging activities using derivatives.activities.


Property, Plant and Equipment - Our properties are stated at cost, including AFUDC and capitalized interest. In some cases, the cost of regulated property retired or sold, plus removal costs, less salvage, is charged to accumulated depreciation. Gains and losses from sales or transfers of nonregulated properties or an entire operating unit or system of our regulated properties are recognized in income. Maintenance and repairs are charged directly to expense.


The interest portion of AFUDC and capitalized interest represent the cost of borrowed funds used to finance construction activities for regulated and nonregulated projects, respectively. We capitalize interest costs during the construction or upgrade of qualifying assets. These costs are recorded as a reduction to interest expense. The equity portion of AFUDC represents the capitalization of the estimated average cost of equity used during the construction of major projects and is recorded in the cost of our regulated properties and as a credit to the allowance for equity funds used during construction.


Our properties are depreciated using the straight-line method over their estimated useful lives. Generally, we apply composite depreciation rates to functional groups of property having similar economic circumstances. We periodically conduct depreciation studies to assess the economic lives of our assets. For ONEOK Partners’our regulated assets, these depreciation studies are

completed as a part of our rate proceedings or tariff filings, and the changes in economic lives, if applicable, are implemented prospectively when the new rates are billed.approved. For our nonregulated assets, if it is determined that the estimated
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economic life changes, the changes are made prospectively. Changes in the estimated economic lives of our property, plant and equipment could have a material effect on our financial position or results of operations.


Property, plant and equipment on our Consolidated Balance Sheets includes construction work in process for capital projects that have not yet been placed in service and therefore are not being depreciated. Assets are transferred out of construction work in process when they are substantially complete and ready for their intended use.


See Note ED for disclosures of our property, plant and equipment.equipment disclosures.


Impairment of Goodwill and Long-Lived Assets, Including Intangible Assets - We assess our goodwill for impairment at least annually on July 1, unless events or changes in circumstances indicate an impairment may have occurred before that time. As the commodity-price environment has remained relatively low since 2015, we elected to perform a quantitative assessment, or Step 1 analysis, to test our goodwill for impairment. The assessment included our current commodity price assumptions, expected contractual terms, anticipated operating costs and volume estimates. Our qualitative goodwill impairment analysis performed as of July 1, 2016,2019, did not result in an impairment charge nor did our analysis reflect any reporting units at risk. In each reporting unit, the fair value substantially exceeded the carrying value. Subsequentrisk, and subsequent to that date, no event has occurred indicating that the implied fair value of each of our reporting units is less than the carrying value of its net assets.


As part of our goodwill impairment test, we may first assess qualitative factors (including macroeconomic conditions, industry and market considerations, cost factors and overall financial performance) to determine whether it is more likely than not that the fair value of each of our reporting units is less than its carrying amount. If further testing is necessary or a quantitative test is elected, we perform a two-step impairment test for goodwill. In the first step, an initial assessment is made by comparing the fair value of a reporting unit with its book value, including goodwill. If the fair value is less than the book value, an impairment is indicated, and we must perform a second test to measure the amount of the impairment. In the second test, we calculate the implied fair value of the goodwill by deducting the fair value of all tangible and intangible net assets of the reporting unit from the fair value determined in step one of the assessment. If the carrying value of the goodwill exceeds the implied fair value of the goodwill, we will record an impairment charge.


Update - Upon adoption of ASU 2017-04 in January 2020, the requirement to calculate the implied fair value of goodwill under the two-step impairment test was eliminated. See “Recently Issued Accounting Standards Update” table below for more information.

To estimate the fair value of our reporting units, we use two generally accepted valuation approaches, an income approach and a market approach, using assumptions consistent with a market participant’s perspective. Under the income approach, we use anticipated cash flows over a period of years plus a terminal value and discount these amounts to their present value using appropriate discount rates. Under the market approach, we apply EBITDA multiples to forecasted EBITDA. The multiples used are consistent with historical asset transactions. The forecasted cash flows are based on average forecasted cash flows for a reporting unit over a period of years.

As part of our indefinite-lived intangible asset impairment test, we first assess qualitative factors similar to those considered in the goodwill impairment test to determine whether it is more likely than not that the indefinite-lived intangible asset was impaired. If further testing is necessary, we compare the estimated fair value of our indefinite-lived intangible asset with its book value. The fair value of our indefinite-lived intangible asset is estimated using the market approach. Under the market approach, we apply multiples to forecasted cash flows of the assets associated with our indefinite-lived intangible asset. The multiples used are consistent with historical asset transactions. After assessing qualitative and quantitative factors, we determined that there were no impairments to our indefinite-lived intangible asset in 2016. There were also no impairment charges resulting from our 2015 and 2014 annual impairment tests.


We assess our long-lived assets including intangible assets with finite useful lives, for impairment whenever events or changes in circumstances indicate that an asset’s carrying amount may not be recoverable. An impairment is indicated if the carrying amount of a long-lived asset exceeds the sum of the undiscounted future cash flows expected to result from the use and eventual disposition of the asset. If an impairment is indicated, we record an impairment loss equal to the difference between the carrying value and the fair value of the long-lived asset.


For the investments we account for under the equity method, the impairment test considers whether the fair value of the equity investment as a whole, not the underlying net assets, has declined and whether that decline is other than temporary. Therefore, we periodically reevaluateevaluate the amount at which we carry our equity-method investments to determine whether current events or circumstances warrant adjustments to our carrying values.


See Notes D, E F and NM for our long-lived assets, goodwill and intangible assets and investments in unconsolidated affiliates disclosures.


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Regulation - ONEOK Partners’ intrastateDepending on the specific service provided, our natural gas transmission pipelines, NGL pipelines and certain natural gas liquids pipelinesstorage facilities are subject to the rate regulation andand/or accounting requirements by one or more of the FERC, OCC, KCC RRC and various municipalities in Texas. ONEOK Partners’ interstate natural gas and natural gas liquids pipelines are subject to regulation by the FERC. In Kansas and Texas, natural gas storage may be regulated by the state and the FERC for certain typesRRC. Accordingly, portions of services. Portions of theour Natural Gas Liquids and Natural Gas Pipelines segments follow the accounting and reporting guidance for regulated operations. In our Consolidated Financial Statements and our Notes to Consolidated Financial Statements, regulated operations are defined pursuant to Financial Accounting Standards Board’s (FASB) Accounting Standards Codification (ASC)ASC 980, Regulated Operations. During the rate-making process for certain of ONEOK Partners’our assets, regulatory authorities set the framework for what ONEOK Partnerswe can charge customers for itsour services and establish the manner that itsour costs are accounted for, including allowing ONEOK Partners us

to defer recognition of certain costs and permitting recovery of the amounts through rates over time as opposed to expensing such costs as incurred. Certain examples of types of regulatory guidance include costs for fuel and losses, acquisition costs, contributions in aid of construction, charges for depreciation, and gains or losses on disposition of assets. This allows ONEOK Partnersus to stabilize rates over time rather than passing such costs on to the customer for immediate recovery. Actions by regulatory authorities could have an effect on the amount recovered from rate payers.amounts we may charge our customers. Any difference in the amount recoverable and the amount deferred is recorded as income or expense at the time of the regulatory action. A write-off of regulatory assets and costs not recovered may be required if all or a portion of the regulated operations have rates that are no longer:
longer (i) established by independent, third-party regulators;
designed to recover the specific entity’s costs of providing regulated services;regulators and
(ii) set at levels that will recover our costs when considering the demand and competition for our services.


At December 31, 2016Retirement and 2015, we recorded regulatory assets of approximately $5.5 million and $5.8 million, respectively, which are currently being recovered and are expected to be recovered from ONEOK Partners’ customers. Regulatory assets are being recovered as a result of approved rate proceedings over varying time periods up to 50 years. These assets are reflected in other assets on our Consolidated Balance Sheets.

Pension andOther Postretirement Employee Benefits - We have a defined benefit retirement planplans covering certain full-timeemployees and former employees. We sponsor welfare plans that provide postretirement medical and life insurance benefits to certain employees hired prior to 2017 who retire with at least five years of service. The expense and liability related to these plans is calculated using statistical and other factors that attempt to anticipate future events. These factors include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, mortality and employment length. In determining the projected benefit obligations and costs, assumptions can change from period to period and may result in material changes in the costs and liabilities we recognize.

See Note LK for more discussion of pensionour retirement and other postretirement employee benefits.benefits disclosures.


Income Taxes -Deferred income taxes are provided for the difference between the financial statement and income tax basis of assets and liabilities and carryforward items based on income tax laws and rates existing at the time the temporary differences are expected to reverse. Generally, the effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date of the rate change. For regulated companies, the effect on deferred tax assets and liabilities of a change in tax rates is recorded as regulatory assets and regulatory liabilities in the period that includes the enactment date, if, as a result of an action by a regulator, it is probable that the effect of the change in tax rates will be recovered from or returned to customers through future rates.


We utilize a more-likely-than-not recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position that is taken or expected to be taken in a tax return. We reflect penalties and interest as part of income tax expense as they become applicable for tax provisions that do not meet the more-likely-than-not recognition threshold and measurement attribute. During 2016, 20152019, 2018 and 20142017, ourwe had no uncertain tax positions did not require anthat required the establishment of a material reserve.


We utilize the “with-and-without” approach for intra-period tax allocation for purposes of allocating total tax expense (or benefit) for the year among the various financial statement components.


We file numerous consolidated and separate income tax returns with federal tax authorities of the United States along with the tax authorities of several states. ThereWe are nonot under any United States federal audits or statute waivers at this time.

See Note ML for additional discussion ofour income taxes.taxes disclosures.


Asset Retirement Obligations - Asset retirement obligations represent legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development and/or normal use of the asset. Certain long-lived assets that comprise ONEOK Partners’of our natural gas gathering and processing, natural gas liquidsNGL and natural gas pipeline facilities are
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subject to agreements or regulations that give rise to our asset retirement obligations for removal or other disposition costs associated with retiring the assets in place upon the discontinued use of the assets. We recognize the fair value of a liability for an asset-retirementasset retirement obligation in the period when it is incurred if a reasonable estimate of the fair value can be made. We are not able to estimate reasonably the fair value of the asset retirement obligations for portions of ONEOK Partners’our assets, primarily certain pipeline assets, because the settlement dates are indeterminable given theour expected continued use of the assets with proper maintenance. We expect ONEOK Partners’our pipeline assets, for which we are unable to estimate reasonably the fair value of the asset retirement obligation, will continue in operation as long as supply and demand for natural gas and natural gas liquids exists.NGLs exist. Based on the widespread use of natural gas for heating and cooking activities for residential users and electric-power generation for commercial users, as well as use of natural gas liquidsNGLs by the petrochemical industry, we expect supply and demand to exist for the foreseeable future.


For our assets that we are able to make an estimate, the fair value of the liability is added to the carrying amount of the associated asset, and this additional carrying amount is depreciated over the life of the asset. The liability is accreted at the end of each period through charges to operating expense. If the obligation is settled for an amount other than the carrying amount of the liability, we will recognize a gain or loss on settlement. The depreciation and accretion expense are immaterial to our consolidated financial statements.Consolidated Financial Statements.


In accordance with long-standing regulatory treatment, ONEOK Partners collects, through rates, the estimated costs of removal on certain regulated properties through depreciation expense, with a corresponding credit to accumulated depreciation and amortization. These removal costs collected through rates include legal and nonlegal removal obligations; however, the amounts collected in excess of the asset-removal costs incurred are accounted for as a regulatory liability for financial reporting purposes. Historically, the regulatory authorities that have jurisdiction over our regulated operations have not required us to quantify this amount; rather, these costs are addressed prospectively in depreciation rates and are set in each general rate order. We have made an estimate of our regulatory liability using current rates since the last general rate order in each of our jurisdictions; however, for financial reporting purposes, significant uncertainty exists regarding the ultimate disposition of this regulatory liability, pending, among other issues, clarification of regulatory intent. We continue to monitor regulatory requirements, and the liability may be adjusted as more information is obtained.

Contingencies -Our accounting for contingencies covers a variety of business activities, including contingencies for legal and environmental exposures. We accrue these contingencies when our assessments indicate that it is probable that a liability has been incurred or an asset will not be recovered and an amount can be estimated reasonably. We expense legal fees as incurred and base our legal liability estimates on currently available facts and our estimates of the ultimate outcome or resolution. Accruals for estimated losses from environmental remediation obligations generally are recognized no later than completion of a remediation feasibility study. Recoveries of environmental remediation costs from other parties are recorded as assets when their receipt is deemed probable. Our expenditures for environmental evaluation, mitigation, remediation and compliance to date have not been significant in relation to our financial position or results of operations, and our expenditures related to environmental matters had no material effect on earnings or cash flows during 2016, 20152019, 2018 and 2014.2017. Actual results may differ from our estimates resulting in an impact, positive or negative, on earnings.

See Note PN for additional discussion of contingencies.


Share-Based Payments - We expense the fair value of share-based payments net of estimated forfeitures. We estimate forfeiture rates based on historical forfeitures under our share-based payment plans.


See Note J for our share-based payments disclosures.

Earnings per Common Share - Basic EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period, vested restricted and performance units that have been deferred and share awards deferred under the compensation plan for non-employeenonemployee directors. Diluted EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period plus potentially dilutive components. The dilutive components are calculated based on the dilutive effect for each quarter. For fiscal-year periods, the dilutive components for each quarter are averaged to arrive at the fiscal year-to-date dilutive component.

See Note I for our earnings per share disclosures.

Segment Reporting - Our chief operating decision-maker reviews the financial performance of each of our three segments, as well as our financial performance as a whole, on a regular basis. Adjusted EBITDA by segment is utilized in this evaluation. We believe this financial measure is useful to investors because it and similar measures are used by many companies in our industry as a measurement of financial performance and are commonly employed by financial analysts and others to evaluate our financial performance and to compare financial performance among companies in our industry. Adjusted EBITDA for each segment is defined as net income adjusted for interest expense, depreciation and amortization, noncash impairment charges, income taxes, allowance for equity funds used during construction, noncash compensation expense, and other noncash items. This calculation may not be comparable with similarly titled measures of other companies.

See Note Q for our segments disclosures.

Reclassifications - Certain reclassifications have been made in the prior-year financial statements to conform to the current-year presentation.


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Recently Issued Accounting Standards Update - Changes to GAAP are established by the FASB in the form of ASUs to the FASB Accounting Standards Codification. We consider the applicability and impact of all ASUs. ASUs not listed below were assessed and determined to be either not applicable or clarifications of ASUs previously issued or listed below. The following tables provide a brief description of recent accounting pronouncements and our analysis of the effects on our financial statements:
Standard Description Date of Adoption Effect on the Financial Statements or Other Significant Matters
Standards that were adopted as of December 31, 2019    
ASU 2015-16, “Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments”The standard requires that an acquirer recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined.First quarter 2016There was no impact, but it could impact us in the future if we complete any acquisitions with subsequent measurement period adjustments.
ASU 2015-07, “Fair Value Measurement (Topic 820): Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)”The standard removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value per share practical expedient. The amendment also removes the requirement to make certain disclosures for all investments that are eligible to be measured at fair value using the net asset value per share practical expedient.First quarter 2016The impact of adopting this standard was not material.
ASU 2015-05, “Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement”The standard clarifies whether a cloud computing arrangement includes a software license. If it does, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses; if not, the customer should account for the arrangement as a service contract.First quarter 2016The impact of adopting this standard was not material.
ASU 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis”The standard eliminates the presumption that a general partner should consolidate a limited partnership. It also modifies the evaluation of whether limited partnerships are variable interest entities or voting interest entities and adds requirements that limited partnerships must meet to qualify as voting interest entities.First quarter 2016As a result of adopting this standard, we no longer consolidate ONEOK Partners under the presumption that a general partner should consolidate a limited partnership. We concluded, however, that ONEOK Partners is a VIE and ONEOK is the primary beneficiary, and we therefore consolidate ONEOK Partners under the variable interest model of consolidation. There was no financial statement impact due to the change in consolidation methodology. See Note O for additional information.
ASU 2014-15, “Presentation of Financial Statements- Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”This standard provides guidance on determining when and how to disclose going-concern uncertainties in the financial statements. The new standard requires management to perform interim and annual assessments of an entity’s ability to continue as a going concern within one year of the date the financial statements are issued. An entity must provide certain disclosures if conditions or events raise substantial doubt about the entity’s ability to continue as a going concern.Fourth quarter 2016
The impact of adopting this standard was not material.

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StandardDescriptionDate of AdoptionEffect on the Financial Statements or Other Significant Matters
Standards that are not yet adopted
ASU 2015-11, “Inventory (Topic 330): Simplifying the Measurement of Inventory”The standard requires that inventory, excluding inventory measured using last-in, first-out (LIFO) or the retail inventory method, be measured at the lower of cost or net realizable value.First quarter 2017We do not expect the adoption of this standard to materially impact us.
ASU 2016-05, “Derivatives and Hedging (Topic 815): Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships”The standard clarifies that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument under Topic 815 does not, in and of itself, require dedesignation of that hedging relationship provided that all other hedge accounting criteria continue to be met.First quarter 2017We do not expect the adoption of this standard to materially impact us.
ASU 2016-06, “Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments”The standard clarifies the requirements for assessing whether a contingent call (put) option that can accelerate the payment of principal on a debt instrument is clearly and closely related to its debt host.First quarter 2017We do not expect the adoption of this standard to materially impact us.
ASU 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting”The standard provides simplified accounting for share-based payment transactions in relation to income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows.First quarter 2017As a result of adopting this guidance, we expect to record an adjustment increasing beginning retained earnings and deferred tax assets in the first quarter 2017 of approximately $73 million to recognize previously unrecognized cumulative excess tax benefits related to share-based payments on a modified retrospective basis.  Prospectively, all share-based payment tax effects will be recorded in earnings.  We do not expect the other effects of adopting this standard to materially impact us.
ASU 2014-09, “Revenue from Contracts with Customers (Topic 606)”The standard outlines the principles an entity must apply to measure and recognize revenue for entities that enter into contracts to provide goods or services to their customers. The core principle is that an entity should recognize revenue at an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring goods or services to a customer. The amendment also requires more extensive disaggregated revenue disclosures in interim and annual financial statements.First quarter 2018We are evaluating the impact of this standard on us. Our evaluation process includes a review of our and ONEOK Partners’ contracts and transaction types across all of the business segments. In addition, we are currently evaluating the methods of adoption and analyzing the impact of the standard on our internal controls, accounting policies and financial statements and disclosures.
ASU 2016-01, “Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities”The standard requires all equity investments, other than those accounted for using the equity method of accounting or those that result in consolidation of the investee, to be measured at fair value with changes in fair value recognized in net income, eliminates the available-for-sale classification for equity securities with readily determinable fair values and eliminates the cost method for equity investments without readily determinable fair values.First quarter 2018We are evaluating the impact of this standard on us.
ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments”The standard clarifies the classification of certain cash receipts and cash payments on the statement of cash flows where diversity in practice has been identified.First quarter 2018We are evaluating the impact of this standard on us.
ASU 2016-02, “Leases (Topic 842)” The standard requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. It also requires qualitative disclosures along with specific quantitative disclosures by lessees and lessors to meet the objective of enabling users of financial statements to assess the amount, timing and uncertainty of cash flows arising from leases. First quarter 2019 We are evaluating our current leasesadopted this standard on January 1, 2019, using the modified retrospective method and the optional transition method to record the adoption impact through a cumulative adjustment to equity. On January 1, 2019, we recorded an immaterial cumulative effect for the adoption of the new standard and recorded $17.5 million of right-of-use assets and $17.4 million of lease liabilities related to operating leases that were not previously recorded on our internal controls, accounting policiesConsolidated Balance Sheets. Our finance lease assets and financial statementsliabilities at January 1, 2019, of $28.1 million and $28.0 million, respectively, did not change as a result of adopting this standard. See Note O for additional disclosures.
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StandardASU 2018-07, “Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting” DescriptionThe standard aligns the measurement and classification guidance for share-based payments to nonemployees with the guidance for share-based payments to employees, with certain exceptions. Date of AdoptionFirst quarter 2019
 Effect on the Financial Statements or Other Significant MattersThe impact of adopting this standard was not material.
Standards that are not yet adopted (continued)as of December 31, 2019  
ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” The standard requires a financial asset (or a group of financial assets) measured at amortized cost basis to be presented net of the allowance for credit losses to reflect the net carrying value at the amount expected to be collected on the financial asset; and the initial allowance for credit losses for purchased financial assets, including available-for-sale debt securities, to be added to the purchase price rather than being reported as a credit loss expense. First quarter 2020 We are evaluatingadopted this standard in January 2020, and the impact of adopting this standard on us.was not material.
ASU 2017-04, “Intangibles- Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” The standard simplifies the subsequent measurement of goodwill by eliminating the requirement to calculate the implied fair value of goodwill under step 2. Instead, an entity will recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. The standard does not change step zero or step 1 assessments. First quarter 2020 
We are evaluatingadopted this standard in January 2020, and the impact of adopting this standard onwas not material.

ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes”The standard simplifies certain concepts in Topic 740, Income Taxes.First quarter 2021We do not expect the adoption of this standard to materially impact us.



B.ACQUISITION OF ONEOK PARTNERS

On January 31, 2017, we and ONEOK Partners entered into the Merger Agreement in which we will acquire all of ONEOK Partners’ outstanding common units representing limited partner interests in ONEOK Partners not already directly or indirectly owned by us in an all stock-for-unit transaction at a ratio of 0.985 of our common shares per common unit of ONEOK Partners, in a taxable transaction to ONEOK Partners’ common unitholders. Following completion of the Merger Transaction, all of ONEOK Partners’ outstanding common units will be directly or indirectly owned by us and will no longer be publicly traded. All of our and ONEOK Partners’ outstanding debt is expected to remain outstanding. We and ONEOK Partners expect to enter into a cross guarantee agreement whereby each party to the agreement unconditionally guarantees and becomes liable for the indebtedness of each other party to the agreement.

A Special Committee of our Board of Directors, the Conflicts Committee of the Board of Directors of the general partner of ONEOK Partners and the Board of Directors of the general partner of ONEOK Partners each unanimously approved the Merger Agreement. Subject to customary approvals and conditions, the Merger Transaction is expected to close in the second quarter of 2017. The Merger Transaction is subject to the approval of ONEOK Partners’ common unitholders and the approval by our shareholders of the issuance of ONEOK common shares in the Merger Transaction.

The Merger Agreement contains certain termination rights, including the right for either us or ONEOK Partners, as applicable, to terminate the Merger Agreement if the closing of the transactions contemplated by the Merger Agreement has not occurred on or before September 30, 2017. In the event of termination of the Merger Agreement under certain circumstances, we may be required to pay ONEOK Partners a termination fee in the form of a temporary reduction in incentive distributions (up to, in certain instances, $300 million) and, under other certain circumstances, ONEOK Partners may be required to pay us a termination fee of (up to, in certain instances, $300 million in cash).

If the Merger Transaction closes, the expected changes in our ownership interest in ONEOK Partners will be accounted for as an equity transaction pursuant to ASC 810 as we expect to continue to control ONEOK Partners, and no gain or loss will be recognized in our consolidated statements of income resulting from the Merger Transaction. In addition, the tax effects of the Merger Transaction will be reported as adjustments to other assets, deferred income taxes and additional paid-in capital consistent with ASC 740, Income Taxes (ASC 740).

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C.FAIR VALUE MEASUREMENTS


Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements for the periods indicated:
 December 31, 2016 December 31, 2019
 Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net (b) Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net
 
(Thousands of dollars)
 
(Thousands of dollars)
Derivative assets                        
Commodity contracts                        
Financial contracts $1,147
 $
 $4,564
 $5,711
 $(4,760) $951
 $10,892
 $
 $55,557
 $66,449
 $(28,588) $37,861
Interest-rate contracts 
 47,457
 
 47,457
 
 47,457
 
 581
 
 581
 
 581
Total derivative assets $1,147
 $47,457
 $4,564
 $53,168
 $(4,760) $48,408
 $10,892
 $581
 $55,557
 $67,030
 $(28,588) $38,442
                        
Derivative liabilities  
  
  
    
  
            
Commodity contracts  
  
  
    
  
            
Financial contracts $(31,458) $
 $(24,861) $(56,319) $56,319
 $
 $(4,811) $
 $(24,785) $(29,596) $28,588
 $(1,008)
Physical contracts 
 
 (3,022) (3,022) 
 (3,022)
Interest-rate contracts 
 (12,795) 
 (12,795) 
 (12,795) 
 (201,941) 
 (201,941) 
 (201,941)
Total derivative liabilities $(31,458) $(12,795) $(27,883) $(72,136) $56,319
 $(15,817) $(4,811) $(201,941) $(24,785) $(231,537) $28,588
 $(202,949)
(a) - Derivative assets and liabilities are presented in our Consolidated Balance SheetsSheet on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2016,2019, we held no0 cash and posted $67.7$8.8 million of cash with various counterparties, including $51.6 million of cash collateral that is offsetting derivative net liability positions under master-netting arrangements in the table above. The remaining $16.1 million of cash collateral in excess of derivative net liability positionswhich is included in other current assets in our Consolidated Balance Sheets.Sheet.
(b) - Included in other current assets, other assets or other current liabilities in our Consolidated Balance Sheets.


 December 31, 2015 December 31, 2018
 Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net (b) Level 1 Level 2 Level 3 Total - Gross Netting (a) Total - Net
 
(Thousands of dollars)
 
(Thousands of dollars)
Derivative assets  
  
  
    
  
            
Commodity contracts                        
Financial contracts $38,921
 $
 $7,253
 $46,174
 $(42,414) $3,760
 $10,812
 $
 $69,165
 $79,977
 $(32,739) $47,238
Physical contracts 
 
 3,591
 3,591
 
 3,591
 
 
 1,142
 1,142
 
 1,142
Interest-rate contracts 
 19,005
 
 19,005
 
 19,005
Total derivative assets $38,921
 $
 $10,844
 $49,765
 $(42,414) $7,351
 $10,812
 $19,005
 $70,307
 $100,124
 $(32,739) $67,385
                        
Derivative liabilities  
  
  
    
  
  
  
  
  
  
  
Commodity contracts  
  
  
    
  
            
Financial contracts $(4,513) $
 $(3,513) $(8,026) $8,026
 $
 $(2,916) $
 $(29,823) $(32,739) $32,739
 $
Interest-rate contracts 
 (9,936) 
 (9,936) 
 (9,936) 
 (99,260) 
 (99,260) 
 (99,260)
Total derivative liabilities $(4,513) $(9,936) $(3,513) $(17,962) $8,026
 $(9,936) $(2,916) $(99,260) $(29,823) $(131,999) $32,739
 $(99,260)
(a) - Derivative assets and liabilities are presented in our Consolidated Balance SheetsSheet on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2015,2018, we held $34.40 cash and posted $0.8 million of cash fromwith various counterparties, thatwhich is offsetting derivative net asset positions in the table above under master-netting arrangements and had no cash collateral posted.
(b) - Includedincluded in other current assets or other current liabilities in our Consolidated Balance Sheets.Sheet.

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The following table sets forth thea reconciliation of our Level 3 fair value measurements for the periods indicated:
  Years Ended
  December 31,
Derivative Assets (Liabilities) 2019 2018
  
(Thousands of dollars)
Net assets (liabilities) at beginning of period $40,484
 $(32,838)
Total changes in fair value:    
Gains (losses) included in net income (a) 
 (140)
Settlements included in net income (a) (40,344) 29,141
New Level 3 derivatives included in other comprehensive income (loss) (b) 30,627
 37,106
Unrealized change included in other comprehensive income (loss) (b) 5
 7,215
Net assets (liabilities) at end of period $30,772
 $40,484
  Years Ended December 31,
Derivative Assets (Liabilities) 2016 2015
  
(Thousands of dollars)
Net assets (liabilities) at beginning of period $7,331
 $9,285
Total realized/unrealized gains (losses):    
Included in earnings (a) (320) 216
Included in other comprehensive income (loss) (30,330) (2,170)
Net assets (liabilities) at end of period $(23,319) $7,331

(a) - Included in commodity sales revenuesrevenues/cost of sales and fuel in our Consolidated Statements of Income.

(b) - Included in change in fair value of derivatives in our Consolidated Statements of Comprehensive Income.
Realized/unrealized gains (losses) include the realization of derivative contracts through maturity.
During the years ended December 31, 20162019 and 2015, gains2018, there were 0 transfers in or losses included in earnings attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the end of each reporting period were not material.

We recognize transfers into and out of the levels inLevel 3 of the fair value hierarchy as of the end of each reporting period. During the years ended December 31, 2016 and 2015, there were no transfers between levels.hierarchy.


Other Financial Instruments -The approximate fair value of cash and cash equivalents, accounts receivable, accounts payable and short-term borrowings is equal to book value due to the short-term nature of these items. Our cash and cash equivalents are comprisedcomposed of bank and money market accounts and are classified as Level 1. Our short-term borrowings are classified as Level 2 since the estimated fair value of the short-term borrowings can be determined using information available in the commercial paper market.


The estimated fair value of our consolidated long-term debt, including current maturities, was $8.8$13.8 billion and $7.4$9.6 billion at December 31, 20162019 and 2015,2018, respectively. The book value of our consolidated long-term debt, including current maturities, was $8.3$12.5 billion and $8.4$9.4 billion at December 31, 20162019 and 2015,2018, respectively. The estimated fair value of the aggregate of ONEOK’s and ONEOK Partners’ long-term debtsenior notes outstanding was determined using quoted market prices for similar issues with similar terms and maturities. The estimated fair value of our consolidated long-term debt is classified as Level 2.

During 2015 and 2014, ONEOK Partners recorded noncash impairment charges, primarily related to its equity investments in the dry natural gas area of the Powder River Basin. The valuation of these investments required use of significant unobservable inputs. ONEOK Partners used an income approach to estimate the fair value of its investments. ONEOK Partners’ discounted cash flow analysis included the following inputs that are not readily available: a discount rate reflective of its cost of capital and estimated contract rates, volumes, operating and maintenance costs and capital expenditures. The estimated fair value of these investments is classified as Level 3. See Note N for additional information about ONEOK Partners’ equity investments and the impairment charges.


D.C.RISK-MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES


Risk-ManagementRisk-management Activities - We are sensitive to changes in natural gas, crude oil and NGL prices, principally as a result of contractual terms under which these commodities are processed, purchased and sold. We are also subject to the risk of interest-rate fluctuation in the normal course of business. We use physical-forward purchases and sales and financial derivatives to secure a certain price for a portion of our natural gas, condensate and NGL products; to reduce our exposure to commodity price and interest-rate fluctuations; and to achieve more predictable cash flows. We follow established policies and procedures to assess risk and approve, monitor and report our risk-management activities. We have not used these instruments for trading purposes. We are also subject to the risk of interest-rate fluctuation in the normal course of business.

Commodity price risk - Commodity price risk refers to the risk of loss in cash flows and future earnings arising from adverse changes in the price of natural gas, NGLs and condensate. We may use the following commodity derivative instruments to mitigatereduce the near-term commodity price risk associated with a portion of the forecasted sales of these commodities:
Futures contracts - Standardized contracts to purchase or sell natural gas and crude oil for future delivery or settlement under the provisions of exchange regulations;
Forward contracts - Nonstandardized commitments between two parties to purchase or sell natural gas, crude oil or NGLs for future physical delivery. These contracts are typically nontransferable and can only be canceled with the consent of both parties;
Swaps - Exchange of one or more payments based on the value of one or more commodities. These instruments transfer the financial risk associated with a future change in value between the counterparties of the transaction, without also conveying ownership interest in the asset or liability; and
Options - Contractual agreements that give the holder the right, but not the obligation, to buy or sell a fixed quantity of a commodity at a fixed price within a specified period of time. Options may either be standardized and exchange-traded or customized and nonexchange-traded.
Futures contracts - Standardized contracts to purchase or sell natural gas and crude oil for future delivery or settlement under the provisions of exchange regulations;
Forward contracts - Nonstandardized commitments between two parties to purchase or sell natural gas, crude oil or NGLs for future physical delivery. These contracts are typically nontransferable and can only be canceled with the consent of both parties;
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Swaps - Exchange of one or more payments based on the value of one or more commodities. These instruments transfer the financial risk associated with a future change in value between the counterparties of the transaction, without also conveying ownership interest in the asset or liability; and
Options - Contractual agreements that give the holder the right, but not the obligation, to buy or sell a fixed quantity of a commodity at a fixed price within a specified period of time. Options may either be standardized and exchange-traded or customized and nonexchange-traded.


We may also use other instruments including collars to mitigate commodity price risk. A collar is a combination of a purchased put option and a sold call option, which places a floor and a ceiling price for commodity sales being hedged.


TheIn our Natural Gas Gathering and Processing segment, iswe are exposed to commodity price risk as a result of retaining a portion of the commodity sales proceeds associated with itsour POP with fee contracts. Under certain POP with fee contracts, ONEOK Partners’ fee revenuesour fees and POP percentage may increase or decrease if production volumes, delivery pressures or commodity prices change relative to specified thresholds. The Natural Gas Gathering and Processing segmentWe also isare exposed to basis risk between the various production and market locations where it receiveswe buy and sellssell commodities. As part of our hedging strategy, we use the previously described commodity derivative financial instruments and physical-forward contracts to reduce the impact of price fluctuations related to natural gas, NGLs and condensate.


TheIn our Natural Gas Liquids segment, is exposed to location price differential risk,we are primarily as a result of the relative value of NGL purchases at one location and sales at another location. The Natural Gas Liquids segment also is exposed to commodity price risk resulting from the relative values of the various NGL products to each other, the value of NGLs in storage and the relative value of NGLs to natural gas. We are also exposed to location price differential risk as a result of the relative value of NGL purchases at one location and sales at another location, primarily related to our optimization and marketing business. As part of our hedging strategy, we utilize physical-forward contracts and commodity derivative financial instruments to reduce the impact of price fluctuations related to NGLs.


TheIn our Natural Gas Pipelines segment, iswe are exposed to commodity price risk because itsour intrastate and interstate pipelines consume natural gas pipelinesin operations and retain natural gas from itsour customers for operations or as part of itsour fee for services provided. When the amount of natural gas consumed in operations by these pipelines differs from the amount provided by itsour customers, theseour pipelines must buy or sell natural gas, or store or use natural gas from inventory, which can expose themthis segment to commodity price risk depending on the regulatory treatment for this activity. To the extent that commodity price risk in theour Natural Gas Pipelines segment is not mitigated by fuel cost-recovery mechanisms, we may use physical-forward sales or purchases to reduce the impact of natural gas price fluctuations related to natural gas.fluctuations. At December 31, 20162019 and 2015,2018, there were no0 financial derivative instruments with respect to ONEOK Partners’our natural gas pipeline operations.


Interest-rate risk - We manage interest-rate risk through the use of fixed-rate debt, floating-rate debt and interest-rate swaps. Interest-rate swaps are agreements to exchange interest payments at some future point based on specified notional amounts. In January 2016, ONEOK Partners2019, we entered into $625 million of forward-starting interest-rate swaps with notional amounts totaling $1 billion to hedge the variability of its LIBOR-based interest payments, all of which were active swaps as of December 31, 2016. In addition, in June 2016, ONEOK Partners entered into forward-starting interest rate swaps with notional amounts totaling $750 million to hedge the variability of interest payments on a portion of itsour forecasted debt issuances that may result from changes in the benchmark interest rate before the debt is issued, resultingissued. We also settled $1.8 billion of our forward-starting interest-rate swaps related to our underwritten public offering of $1.25 billion senior unsecured notes in totalMarch 2019 and $2.0 billion senior unsecured notes in August 2019.

At December 31, 2019 and 2018, we had forward-starting interest-rate swaps with notional amounts totaling $1.8 billion and $3.0 billion, respectively, to hedge the variability of this typeinterest payments on a portion of interest-rate swap of $1.2 billion atour forecasted debt issuances. At December 31, 2016, compared2019 and 2018, we had interest-rate swaps with $400 million at December 31, 2015.notional amounts totaling $1.3 billion to hedge the variability of our LIBOR-based interest payments. All of ONEOK Partners’our interest-rate swaps are designated as cash flow hedges. Upon ONEOK Partners’ debt issuance in March 2015, ONEOK Partners settled $500 million of its interest-rate swaps and realized a loss of $55.1 million, which is included in accumulated other comprehensive loss and will be amortized to interest expense over the term of the related debt.


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Fair Values of Derivative Instruments - All derivatives measured at fair value at December 31, 2019 and 2018, were designated as hedging instruments. See Note B for a discussion of the inputs associated with our fair value measurements.
The following table sets forth the fair values of our derivative instruments presented on a gross basis for the periods indicated:
  December 31, 2016 December 31, 2015 December 31, 2019 December 31, 2018
Location in our Consolidated Balance Sheets Assets (Liabilities) Assets (Liabilities)Location in our Consolidated Balance Sheets Assets (Liabilities) Assets (Liabilities)
 
(Thousands of dollars)
 
(Thousands of dollars)
Derivatives designated as hedging instruments        Derivatives designated as hedging instruments        
Commodity contracts(a)                
Financial contractsOther current assets/other current liabilities $1,155
 $(49,938) $39,255
 $(1,440)Other current assets $64,858
 $(26,997) $78,891
 $(31,793)
Other assets/deferred credits and other liabilities

 210
 (2,142) 
 
Other assets/other deferred credits 1,591
 (2,599) 1,086
 (946)
Physical contractsOther current assets/other current liabilities 
 (3,022) 3,591
 
Other current assets 
 
 1,142
 
Interest-rate contractsOther assets/other current liabilities 47,457
 (12,795) 
 (9,936)Other current assets/other current liabilities 
 (90,161) 19,005
 (15,012)
Other assets/other deferred credits 581
 (111,780) 
 (84,248)
Total derivatives designated as hedging instruments 48,822
 (67,897) 42,846
 (11,376) $67,030
 $(231,537) $100,124
 $(131,999)
Derivatives not designated as hedging instruments  
  
  
  
Commodity contracts  
  
  
  
Financial contractsOther current assets/other current liabilities 4,346
 (4,239) 6,919
 (6,586)
Total derivatives not designated as hedging instruments 4,346
 (4,239) 6,919
 (6,586)
Total derivatives $53,168
 $(72,136) $49,765
 $(17,962)
(a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us.


Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for derivative instruments held for the periods indicated:
  December 31, 2019 December 31, 2018
 
Contract
Type
Purchased/
Payor
 
Sold/
Receiver
 
Purchased/
Payor
 
Sold/
Receiver
Derivatives designated as hedging instruments:       
Cash flow hedges        
Fixed price        
-Natural gas (Bcf)
Futures and swaps
 (59.0) 
 (29.9)
-Crude oil and NGLs (MMBbl)
Futures, forwards and swaps7.9
 (17.4) 6.5
 (13.8)
Basis        
-Natural gas (Bcf)
Futures and swaps
 (59.0) 
 (29.9)
Interest-rate contracts (Billions of dollars)
Swaps$3.1
 $
 $4.3
 $

  December 31, 2016 December 31, 2015
 
Contract
Type
Purchased/
Payor
 
Sold/
Receiver
 
Purchased/
Payor
 
Sold/
Receiver
Derivatives designated as hedging instruments:       
Cash flow hedges        
Fixed price        
-Natural gas (Bcf)
Futures and swaps
 (38.4) 
 (27.1)
-Natural gas (Bcf)
Put options49.5
 
 
 
-Crude oil and NGLs (MMBbl)
Futures, forwards and swaps
 (3.6) 
 (2.3)
Basis        
-Natural gas (Bcf)
Futures and swaps
 (38.4) 
 (27.1)
Interest-rate contracts (Millions of dollars)
Swaps$2,150.0
 $
 $400.0
 $
Derivatives not designated as hedging instruments:       
Fixed price        
-Natural gas (Bcf)Futures and swaps0.4
 
 
 
-NGLs (MMBbl)
Futures, forwards
and swaps
0.5
 (0.7) 0.6
 (0.6)
Basis

        
-Natural gas (Bcf)
Futures and swaps0.4
 
 
 


These notional amounts are used to summarize the volume of financial instruments; however, they do not reflect the extent to which the positions offset one another and, consequently, do not reflect our actual exposure to market or credit risk.


Cash Flow Hedges-At December 31, 2016, our Consolidated Balance Sheet reflected a net loss of $154.4 million in accumulated other comprehensive loss. The portion of accumulated other comprehensive loss attributable to commodity
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derivative financial instruments is an unrealized loss of $16.5 million, net of tax, which will be realized within the next 24 months as the forecasted transactions affect earnings. If commodity prices remain at current levels, we will realize approximately $16.0 million in net losses, net of tax, over the next 12 months and an immaterial amount of net losses thereafter. The amount deferred in accumulated other comprehensive loss attributable to settled interest-rate swaps is a loss of $43.9 million, net of tax, which will be recognized over the life of the long-term, fixed-rate debt. We expect that losses of $6.4 million, net of tax, will be reclassified into earnings during the next 12 months as the hedged items affect earnings. The remaining amounts in accumulated other comprehensive loss are attributable primarily to forward-starting interest-rate swaps with future settlement dates, which will be amortized to interest expense over the life of long-term, fixed-rate debt upon issuance of the debt.

The following table sets forth the unrealized effectchange in fair value of cash flow hedges recognized in other comprehensive income (loss) for the periods indicated:
Derivatives in Cash Flow Hedging Relationships Years Ended December 31,
 2019 2018 2017
  
(Thousands of dollars)
Commodity contracts $38,819
 $53,217
 $(40,577)
Interest-rate contracts (230,771) (60,584) 163
Total unrealized change in fair value of cash flow hedges in other comprehensive income (loss) $(191,952) $(7,367) $(40,414)

Derivatives in Cash Flow
Hedging Relationships
 Years Ended December 31,
 2016 2015 2014
  
(Thousands of dollars)
Continuing Operations  
Commodity contracts $(78,513) $70,065
 $32,354
Interest-rate contracts 42,761
 (22,565) (96,993)
Total unrealized gain (loss) recognized in other comprehensive income (loss) on derivatives (effective portion) for continuing operations $(35,752) $47,500
 $(64,639)


The following table sets forth the effect of cash flow hedges on our Consolidated Statements of Incomenet income for the periods indicated:
Derivatives in Cash Flow
Hedging Relationships
 
Location of Gain (Loss) Reclassified from
Accumulated Other Comprehensive Loss into
Net Income
      
  Years Ended December 31,
  2019 2018 2017
    
(Thousands of dollars)
Commodity contracts Commodity sales revenues/cost of sales and fuel $50,345
 $(29,596) $(69,561)
Interest-rate contracts Interest expense (23,230) (18,287) (21,025)
Total change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income on derivatives $27,115
 $(47,883) $(90,586)

  
Location of Gain (Loss) Reclassified from
Accumulated Other Comprehensive Income
(Loss) into Net Income (Effective Portion)
  
Derivatives in Cash Flow
Hedging Relationships
  Years Ended December 31,
 2016 2015 2014
    
(Thousands of dollars)
Continuing Operations        
Commodity contracts Commodity sales revenues $26,422
 $81,089
 $(21,052)
Interest-rate contracts Interest expense (19,215) (17,565) (21,966)
Total gain (loss) reclassified from accumulated other comprehensive loss into net income from continuing operations on derivatives (effective portion) $7,207
 $63,524
 $(43,018)


For the year ended December 31, 2014, an unrealized loss of $3.7 million was recognized in other comprehensive income (loss) and a realized loss of $12.8 million was reclassified from accumulated other comprehensive loss into net income related to cash flow hedges for our former energy services business.

Credit Risk - We monitor the creditworthiness of our counterparties and compliance with policies and limits established by our Risk Oversight and Strategy Committee. We maintain credit policies with regard to our counterparties that we believe minimize overall credit risk. These policies include an evaluation of potential counterparties’ financial condition (including credit ratings, bond yields and credit default swap rates), collateral requirements under certain circumstances and the use of standardized master-netting agreements that allow us to net the positive and negative exposures associated with a single counterparty. We have counterparties whose credit is not rated, and for those customers, we use internally developed credit ratings.ratings for counterparties that do not have a credit rating.


From time to time, ONEOK PartnersOur financial commodity derivatives are generally settled through a NYMEX or Intercontinental Exchange (ICE) clearing broker account with daily margin requirements. However, we may enter into financial derivative instruments that contain provisions that require itus to maintain an investment-grade credit rating from S&P and/or Moody’s. If ONEOK Partners’our credit ratings on itsour senior unsecured long-term debt were to decline below investment grade, the counterparties to the derivative instruments could request collateralization on derivative instruments in net liability positions. There were no0 financial derivative instruments with contingent features related to credit risk as ofat December 31, 2016.2019.


The counterparties to our derivative contracts typically consist primarily of major energy companies, financial institutions and commercial and industrial end users. This concentration of counterparties may affect our overall exposure to credit risk, either positively or negatively, in that the counterparties may be affected similarly by changes in economic, regulatory or other

conditions. Based on our policies, exposures, credit and other reserves, we do not anticipate a material adverse effect on our financial position or results of operations as a result of counterparty nonperformance.
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At December 31, 2016,2019, the net credit exposure from our derivative assets is primarily with investment-grade companies in the financial services sector.


E.PROPERTY, PLANT AND EQUIPMENT

D.    PROPERTY, PLANT AND EQUIPMENT

The following table sets forth our property, plant and equipment by property type, for the periods indicated:
  
Estimated Useful
Lives (Years)
 December 31,
2019
 December 31,
2018
    
(Thousands of dollars)
Nonregulated      
Gathering pipelines and related equipment 5 to 40 $4,316,936
 $3,851,043
Processing and fractionation and related equipment 3 to 40 4,439,332
 4,171,072
Storage and related equipment 3 to 54 684,635
 656,455
Transmission pipelines and related equipment 5 to 54 797,678
 782,258
General plant and other 2 to 60 610,013
 547,424
Construction work in process  1,645,663
 797,182
Regulated   

  
Storage and related equipment 5 to 25 9,180
 8,987
Natural gas transmission pipelines and related equipment 5 to 77 1,552,546
 1,475,789
NGL transmission pipelines and related equipment 5 to 88 6,126,056
 4,677,599
General plant and other 2 to 50 66,507
 61,136
Construction work in process  1,802,946
 1,002,018
Property, plant and equipment   22,051,492
 18,030,963
Accumulated depreciation and amortization - nonregulated   (2,471,649) (2,168,855)
Accumulated depreciation and amortization - regulated   (1,231,158) (1,095,457)
Net property, plant and equipment   $18,348,685
 $14,766,651

  
Estimated Useful
Lives (Years)
 December 31,
2016
 December 31,
2015
    
(Thousands of dollars)
Nonregulated      
Gathering pipelines and related equipment 5 to 40 $3,352,963
 $2,961,388
Processing and fractionation and related equipment 3 to 40 3,831,966
 3,627,062
Storage and related equipment 5 to 54 558,695
 510,820
Transmission pipelines and related equipment 5 to 54 689,804
 598,375
General plant and other 2 to 60 487,559
 448,044
Construction work in process  371,628
 691,907
Regulated    
  
Storage and related equipment 5 to 25 13,524
 22,085
Natural gas transmission pipelines and related equipment 5 to 77 1,345,740
 1,325,235
Natural gas liquids transmission pipelines and related equipment 5 to 88 4,309,341
 4,208,121
General plant and other 2 to 50 54,643
 53,962
Construction work in process  62,634
 83,461
Property, plant and equipment   15,078,497
 14,530,460
Accumulated depreciation and amortization - nonregulated   (1,641,490) (1,396,647)
Accumulated depreciation and amortization - regulated   (865,604) (759,824)
Net property, plant and equipment   $12,571,403
 $12,373,989


The average depreciation rates for ONEOK Partners’our regulated property are set forth, by segment, in the following table for the periods indicated:
  Years Ended December 31,
  2019 2018 2017
Natural Gas Liquids 2.0% 1.9% 1.9%
Natural Gas Pipelines 2.1% 2.1% 2.1%

  Years Ended December 31,
  2016 2015 2014
Natural Gas Liquids 1.9% 1.9% 2.0%
Natural Gas Pipelines 2.1% 2.1% 2.1%


We and ONEOK Partners incurred costs for construction work in process that had not been paid at December 31, 2016, 20152019, 2018 and 2014,2017, of $83.0$544.8 million, $115.7$388.3 million and $187.2$92.4 million, respectively. Such amounts are not included in capital expenditures (less AFUDC and capitalized interest) on the Consolidated Statements of Cash Flows.


Impairment Charges - Due to the continued and greater than expected decline in volumes gathered in the dry natural gas areaIn 2017, following a review of the Powder River Basin,nonstrategic assets for potential divestiture, we evaluated our long-lived assets and equity investments in this area in 2015 and made the decision to cease operationsrecorded $16.0 million of our wholly owned coal-bed methane natural gas gathering system in 2016. This resulted in a $63.5 million noncash impairment charge to long-lived assets in 2015 in the Natural Gas Gathering and Processing segment.

In addition, ONEOK Partners recorded noncash impairment charges of approximately $20.2 million for previously idledrelated to certain nonstrategic gathering and processing assets located in the Natural Gas Gathering and Processing and Natural Gas Liquids segments in 2015, as the expectation for future use of these assets changed.North Dakota.



F.E.GOODWILL AND INTANGIBLE ASSETS


Goodwill - The following table sets forth our goodwill, by segment, for the periods indicated:
  December 31,
2019
 December 31,
2018
  
(Thousands of dollars)
Natural Gas Gathering and Processing $153,404
 $153,404
Natural Gas Liquids 371,217
 371,217
Natural Gas Pipelines 156,375
 156,479
Total goodwill $680,996
 $681,100
  December 31, December 31,
  2016 2015
  
(Thousands of dollars)
Natural Gas Gathering and Processing $122,291
 $122,291
Natural Gas Liquids 268,544
 268,544
Natural Gas Pipelines 134,700
 134,700
Total goodwill $525,535
 $525,535


Intangible Assets - The following table sets forth the gross carrying amount and accumulated amortization ofOur intangible assets for the periods indicated:
  December 31, December 31,
  2016 2015
  
(Thousands of dollars)
Gross intangible assets $581,633
 $581,632
Accumulated amortization (101,809) (89,909)
Net intangible assets $479,824
 $491,723

At December 31, 2016 and 2015, ONEOK Partners had $324.3 million and $336.2 million, respectively, of intangible assets relatedrelate primarily to contracts acquired through acquisitions in theour Natural Gas Gathering and Processing and Natural Gas Liquids segments, which are being amortized over periods of 2015 to 40 years. The remaining intangible asset balance has an indefinite life. Amortization expense for intangible assets for 2016, 2015 and 2014 was $11.9 million $11.9 millionin 2019, 2018 and $11.8 million, respectively,2017, and the aggregate amortization expense for each of the next five years is estimated to be approximately $11.9 million. The following table reflects the gross carrying amount and accumulated amortization of intangible assets for the periods presented:

  December 31,
2019
 December 31,
2018
  
(Thousands of dollars)
Gross intangible assets $414,345
 $411,650
Accumulated amortization (137,508) (125,608)
Net intangible assets $276,837
 $286,042



G.F.DEBT


The following table sets forth our consolidated debt for the periods indicated:
  December 31,
2019
 December 31,
2018
  (Thousands of dollars)
Commercial paper outstanding, bearing a weighted-average interest rate of 2.16% as of December 31, 2019$220,000
 $
Senior unsecured obligations:    
$500,000 at 8.625% due March 2019 
 500,000
$300,000 at 3.8% due March 2020 
 300,000
$1,500,000 term loan, rate of 2.70% and 3.63% as of December 31, 2019 and 2018, respectively, due November 2021 1,250,000
 550,000
$700,000 at 4.25% due February 2022 547,397
 547,397
$900,000 at 3.375 % due October 2022 900,000
 900,000
$425,000 at 5.0 % due September 2023 425,000
 425,000
$500,000 at 7.5% due September 2023 500,000
 500,000
$500,000 at 2.75% due September 2024 500,000
 
$500,000 at 4.9 % due March 2025 500,000
 500,000
$500,000 at 4.0% due July 2027 500,000
 500,000
$800,000 at 4.55% due July 2028 800,000
 800,000
$100,000 at 6.875% due September 2028 100,000
 100,000
$700,000 at 4.35% due March 2029 700,000
 
$750,000 at 3.4% due September 2029 750,000
 
$400,000 at 6.0% due June 2035 400,000
 400,000
$600,000 at 6.65% due October 2036 600,000
 600,000
$600,000 at 6.85% due October 2037 600,000
 600,000
$650,000 at 6.125% due February 2041 650,000
 650,000
$400,000 at 6.2% due September 2043 400,000
 400,000
$700,000 at 4.95% due July 2047 700,000
 700,000
$1,000,000 at 5.2% due July 2048 1,000,000
 450,000
$750,000 at 4.45% due September 2049 750,000
 
Guardian Pipeline    
Weighted average 7.85% due December 2022 21,307
 28,957
Total debt 12,813,704
 9,451,354
Unamortized portion of terminated swaps 15,032
 16,750
Unamortized debt issuance costs and discounts (121,329) (87,120)
Current maturities of long-term debt (7,650) (507,650)
Short-term borrowings (a) (220,000) 
Long-term debt $12,479,757
 $8,873,334
  December 31,
2016
 December 31,
2015
  
(Thousands of dollars)
ONEOK    
Borrowings outstanding under the ONEOK Credit Agreement (a)
 $
 $
Senior unsecured obligations:    
$700,000 at 4.25% due 2022 547,397
 547,397
$500,000 at 7.5% due 2023 500,000
 500,000
$100,000 at 6.5% due 2028 87,126
 87,516
$100,000 at 6.875% due 2028 100,000
 100,000
$400,000 at 6.0% due 2035 400,000
 400,000
Total ONEOK senior notes payable 1,634,523
 1,634,913
ONEOK Partners    
Borrowings outstanding under the ONEOK Partners Credit Agreement at 1.60% as of
December 31, 2015 (b)
 
 300,000
Commercial paper outstanding, bearing a weighted-average interest rate of 1.27% and 1.23%, respectively 1,110,277
 246,340
Senior unsecured obligations:    
$650,000 at 3.25% due 2016 
 650,000
$450,000 at 6.15% due 2016 
 450,000
$400,000 at 2.0% due 2017 400,000
 400,000
$425,000 at 3.2% due 2018 425,000
 425,000
$1,000,000 term loan, variable rate, due 2019 1,000,000
 
$500,000 at 8.625% due 2019 500,000
 500,000
$300,000 at 3.8% due 2020 300,000
 300,000
$900,000 at 3.375 % due 2022 900,000
 900,000
$425,000 at 5.0 % due 2023 425,000
 425,000
$500,000 at 4.9 % due 2025 500,000
 500,000
$600,000 at 6.65% due 2036 600,000
 600,000
$600,000 at 6.85% due 2037 600,000
 600,000
$650,000 at 6.125% due 2041 650,000
 650,000
$400,000 at 6.2% due 2043 400,000
 400,000
Guardian Pipeline  
  
Average 7.88% due 2022 44,257
 51,907
Total debt 9,489,057
 9,033,160
Unamortized portion of terminated swaps 20,186
 21,904
Unamortized debt issuance costs and discounts (68,320) (74,492)
Current maturities of long-term debt (410,650) (110,650)
Short-term borrowings (c)
 (1,110,277) (546,340)
Long-term debt $7,919,996
 $8,323,582

(a) - ONEOK had $1.1 million of letters of credit issued at December 31, 2016 and 2015.
(b) - ONEOK Partners had $14 million of letters of credit issued at December 31, 2016 and 2015.
(c) - Individual issuances of commercial paper under ONEOK Partners’ $2.4 billionour commercial paper program generally mature in 90 days or less. However, these issuances are supported by and reduce the borrowing capacity under the ONEOK Partners Credit Agreement.


ONEOK$2.5 Billion Credit Agreement- In January 2016,May 2019, we extended the term of the ONEOKour $2.5 Billion Credit Agreement by one year to January 2020. The ONEOKJune 2024. Our $2.5 Billion Credit Agreement is a $300 million revolving credit facility and contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining a ratio of indebtedness to consolidated EBITDA (EBITDA, as defined in our ONEOK Credit Agreement) of no more than 4.0 to 1. Upon breach of certain covenants by us in our ONEOK Credit Agreement, amounts outstanding under our ONEOK Credit Agreement, if any, may become due and payable immediately. At December 31, 2016, ONEOK’s ratio of indebtedness to consolidated EBITDA was 2.2 to 1, and ONEOK was in compliance with all covenants under the ONEOK Credit Agreement.


The ONEOK Credit Agreement includes a $50 million sublimit for the issuance of standby letters of credit and a $50 million sublimit for swingline loans. Under the terms of the ONEOK Credit Agreement, ONEOK may request an increase in the size of the facility to an aggregate of $500 million from $300 million by either commitments from new lenders or increased commitments from existing lenders. The ONEOK Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in our credit rating. Based on our current credit rating, borrowings, if any, will accrue interest at LIBOR plus 145 basis points, and the annual facility fee is 30 basis points.

ONEOK Partners Credit Agreement - In January 2016, ONEOK Partners extended the term of the ONEOK Partners Credit Agreement by one year to January 2020. The ONEOK Partners Credit Agreement is a $2.4 billion revolving credit facility and includes a $100 million sublimit for the issuance of standby letters of credit and a $150 million swingline sublimit. The ONEOK Partners Credit Agreement is available for general partnership purposes and had available capacity of approximately $1.3 billion at December 31, 2016.

The ONEOK Partners Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in our credit rating. Under the terms of the ONEOK Partners Credit Agreement, based on ONEOK Partners’ current credit ratings, borrowings, if any, will accrue interest at LIBOR plus 117.5 basis points, and the annual facility fee is 20 basis points. The ONEOK Partners Credit Agreement is guaranteed fully and unconditionally by the Intermediate Partnership. Borrowings under the ONEOK Partners Credit Agreement are nonrecourse to ONEOK. Following the completion of the Merger Transaction described in Note B, we and ONEOK Partners expect to enter into a cross guarantee agreement whereby each party to the agreement unconditionally guarantees and becomes liable for the indebtedness of each other party to the agreement.

The ONEOK Partners Credit Agreement contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining a ratio of indebtedness to adjusted EBITDA (EBITDA, as defined in the ONEOK Partnersour $2.5 Billion Credit Agreement, adjusted for all noncash charges and increased for projected EBITDA from certain lender-approved capital expansion projects) of no more than 5.0 to 1.1 at December 31, 2019. If ONEOK Partners consummateswe consummate one or more acquisitions in which the aggregate purchase price is $25 million or more, the allowable ratio of indebtedness to adjusted EBITDA will increase to 5.5 to 1 for the quarter in which the acquisition wasis completed and the following two following quarters. If ONEOK Partners wereThereafter, the covenant will decrease to breach certain covenants5.0 to 1.

Our $2.5 Billion Credit Agreement includes a $100 million sublimit for the issuance of standby letters of credit and a $200 million sublimit for swingline loans. Under the terms of our $2.5 Billion Credit Agreement, we may request an increase in the ONEOK Partnerssize of the facility to an aggregate of $3.5 billion by either commitments from new lenders or increased commitments from existing lenders. Our $2.5 Billion Credit Agreement amounts outstanding under the ONEOK Partners Credit Agreement,contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in our credit ratings. Based on our current credit ratings, borrowings, if any, may become duewill accrue at LIBOR plus 110 basis points, and payable immediately.the annual facility fee is 15 basis points. At December 31, 2016, ONEOK Partners’2019, our ratio of indebtedness to adjusted EBITDA was 4.1 to 1, and it waswe were in compliance with all covenants under the ONEOK Partnersour $2.5 Billion Credit Agreement.


At December 31, 2019 and 2018, we had letters of credit issued totaling $4.7 million and $1.4 million, respectively, and 0 borrowings outstanding under our $2.5 Billion Credit Agreement.

Senior Unsecured Obligations - All notes are senior unsecured obligations, ranking equally in right of payment with all of our existing and future unsecured senior indebtedness, and are structurally subordinate to any of the existing and future debt and other liabilities of any nonguarantor subsidiaries.


ONEOK issuanceIssuances - In August 2015,2019, we completed an underwritten public offering of $2.0 billion senior unsecured notes consisting of $500 million, 7.5 percent2.75% senior notes due 2023. 2024; $750 million, 3.4% senior notes due 2029; and$750 million,4.45% senior notes due 2049. The net proceeds, after deducting underwriting discounts, commissions and otheroffering expenses, were approximately $487.1 million. We $1.97 billion. The proceeds were used the proceeds together with cash on hand to purchase $650for general corporate purposes, including repayment of existing indebtedness and funding capital expenditures.

In March 2019, we completed an underwritten public offering of $1.25 billion senior unsecured notes consisting of $700 million, of additional common units from ONEOK Partners.

ONEOK repayment-In February 2014, we retired approximately $152.5 million of the 4.25 percent4.35% senior notes due 2022 through a tender offer. The total amount paid, including fees2029 and other charges, was approximately $150 million. In March 2014, we repaidan additional issuance of $550 million of our $400 million, 5.2 percentexisting 5.2% senior notes due in 20152048. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, and exclusive of accrued interest, were $1.23 billion. The proceeds were used for a totalgeneral corporate purposes, including repayment of $430.1 million, including accrued but unpaid interest to the redemption date. We recorded a loss on extinguishment of $24.8 million related to the debt retirements, which is included in other expense in our Consolidated Statements of Income.existing indebtedness and funding capital expenditures.


ONEOK Partners issuances and maturities - In January 2016, ONEOK PartnersNovember 2018, we entered into the $1.0 billion senior unsecuredour $1.5 Billion Term Loan Agreement with a syndicate of banks. Thebanks, which was fully drawn as of June 30, 2019. We repaid $250 million of our outstanding balance in August 2019 and have $1.25 billion drawn as of December 31, 2019. Our $1.5 Billion Term Loan Agreement matures in January 2019November 2021 and bears interest at LIBOR plus 130112.5 basis points based on ONEOK Partners’our current credit ratings. At December 31, 2016, the interest rate was 2.04 percent percent. The Term Loan Agreementagreement contains an option, which may be exercised up to two times, to extend the term of the loan, in each case, for an additional one-year term subject to approval of the banks. TheOur $1.5 Billion Term Loan Agreement allows prepayment of all or any portion outstanding, without penalty or premium. Duringpremium, and contains substantially the first quarter 2016, ONEOK Partners drew the full $1.0 billion available under the agreement andsame covenants as those contained in our $2.5 Billion Credit Agreement. The proceeds were used the proceeds to repay $650 million of senior notes at maturity, to repay amounts outstanding under ONEOK Partners’ commercial paper program and for general partnership purposes.corporate purposes, including repayment of existing indebtedness and funding capital expenditures.

ONEOK Partners repaid its $450 million, 6.15 percent senior notes at maturity in October 2016, with a combination of cash on hand and short-term borrowings.



In March 2015, ONEOK PartnersJuly 2018, we completed an underwritten public offering of $800 million of$1.25 billion senior unsecured notes consisting of $300$800 million, 3.8 percent4.55% senior notes due 2020,2028 and $500$450 million, 4.9 percent5.2% senior notes due 2025.2048. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were approximately $792.3 million. ONEOK Partners$1.23 billion. The proceeds were used the proceeds to repay amounts outstanding under its commercial paper program and for general partnership purposes.corporate purposes, which included repayment of existing indebtedness and funding capital expenditures.

In July 2017, we completed an underwritten public offering of $1.2 billion senior unsecured notes consisting of $500 million, 4.0% senior notes due 2027, and $700 million, 4.95% senior notes due 2047. The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $1.2 billion. The proceeds were used for general corporate purposes, which included repayment of existing indebtedness and funding capital expenditures.

Repayments - In September 2019, we redeemed our $300 million, 3.8% senior notes due March 2020 at a redemption price of $308.0 million, including the outstanding principal, plus accrued and unpaid interest, with cash on hand from our public offering of $2.0 billion senior unsecured notes in August 2019. In connection with this early redemption, we incurred a $2.7

ONE Gas issuance- million loss on extinguishment of debt, which is included in other expense in our Consolidated Statements of Income for the year ended December 31, 2019.

In January 2014, ONE Gas, which at the time was our wholly owned subsidiary, completed a private placement of three series of senior notes aggregating $1.2 billion, consisting of $300August 2019, we repaid $250 million of five-yearour $1.5 Billion Term Loan agreement with cash on hand.

In March 2019, we repaid our $500 million, 8.625% senior notes at 2.07 percent; $300maturity with a combination of cash on hand and short-term borrowings.

In 2018, we repaid our $425 million, 3.2% senior notes due September 2018 with cash on hand and the remaining $500 million of 10-yearthe ONEOK Partners Term Loan Agreement due 2019 with a combination of cash on hand and short-term borrowings.

In 2017, we repaid ONEOK Partners’ $400 million, 2.0% senior notes at 3.61 percent;due in October 2017 and $600repaid $500 million of 30-yearthe ONEOK Partners Term Loan Agreement due 2019 with a combination of cash on hand and short-term borrowings and redeemed our 6.5% senior notes due 2028 at 4.658 percent. ONE Gas received approximately $1.19 billion from the offering, neta redemption price of issuance costs. Our obligations related to the ONE Gas Senior Notes terminated in connection$87.0 million with the completion of the separation of ONE Gas.cash on hand.


The aggregate maturities of long-term debt outstanding as of December 31, 2016,2019, for the years 20172020 through 20212024 are shown below:
  
Senior Unsecured
Obligations
 
Guardian
Pipeline
 Total
  (Millions of dollars)
2020 $
 $7.7
 $7.7
2021 $1,250.0
 $7.7
 $1,257.7
2022 $1,447.4
 $5.9
 $1,453.3
2023 $925.0
 $
 $925.0
2024 $500.0
 $
 $500.0
 ONEOK 
ONEOK
Partners
 
Guardian
Pipeline
 Total
   
(Millions of dollars)
2017$3.0
 $400.0
 $7.7
 $410.7
2018$3.0
 $425.0
 $7.7
 $435.7
2019$3.0
 $1,500.0
 $7.7
 $1,510.7
2020$3.0
 $300.0
 $7.7
 $310.7
2021$3.0
 $
 $7.7
 $10.7


ONEOKCovenants - Our senior notes are governed by indentures containing covenants, - including among other provisions, limitations on our ability to place liens on our property or assets and to sell and leaseback our property. The indentures governing ONEOK’s 6.5 percent and 6.875 percentour 6.875% senior notes due 2028 include an event of default upon acceleration of other indebtedness of $15 million or more, and the indentures governing the remainder of our senior notes due 2022, 2023 and 2035 include an event of default upon the acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent25% in aggregate principal amount of the outstanding senior notes due 2022, 2023, 2028 and 2035 to declare those senior notes immediately due and payable in full. The indenture for the 7.5% notes due 2023 also contains a provision that allows the holders of the notes to require ONEOK to offer to repurchase all or any part of their notes if a change of control and a credit rating downgrade occur at a purchase price of 101 percent101% of the principal amount, plus accrued and unpaid interest, if any.


ONEOKWe may redeem the 6.875 percentour senior notes, due 2028 and the senior notes due 2035, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOKWe may redeem the 6.5 percent senior notes due 2028, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest. ONEOK may redeem the remaining balance of itsour senior notes due 2022, 2023, 2024, 2025, 2027, 2028 (4.55%), 2029, 2041, 2043, 2047, 2048 and 20232049 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting threeone to six months before the maturity date. Prior to this date ONEOK may redeem these senior notes on the same basis as the 6.875 percent senior notes due 2028 and the senior notes due 2035. The redemption price will never be less than 100 percent of the principal amount ofstipulated in the respective note plus accrued and unpaid interest to the redemption date. ONEOK’scontract terms. Our senior notes are senior unsecured obligations, ranking equally in right of payment with all of ONEOK’sour existing and future unsecured senior indebtedness.


ONEOK Partners covenants - ONEOK Partners’ Term Loan Agreement contains substantially the same covenants as the ONEOK Partners Credit Agreement.

ONEOK Partners’ senior notes are governed by an indenture, dated as of September 25, 2006, between ONEOK Partners and Wells Fargo Bank, N.A., the trustee, as supplemented. The indenture does not limit the aggregate principal amount of debt securities that may be issued and provides that debt securities may be issued from time to time in one or more additional series. The indenture contains covenants including, among other provisions, limitations on ONEOK Partners’ ability to place liens on its property or assets and to sell and lease back its property. The indenture includes an event of default upon acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of any of ONEOK Partners’ outstanding senior notes to declare those notes immediately due and payable in full.

ONEOK Partners may redeem its senior notes due 2019, 2036 and 2037, in whole or in part, at any time prior to their maturity at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The

redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date. ONEOK Partners may redeem its senior notes due 2017 and its senior notes due 2022 at par starting one month and three months, respectively, before their maturity dates. ONEOK Partners may redeem its senior notes due 2041 at a redemption price equal to the principal amount, plus accrued and unpaid interest, starting six months before its maturity date. Prior to that date, ONEOK Partners may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. ONEOK Partners may redeem its senior notes due 2018, 2020, 2023, 2025, and 2043 at par, plus accrued and unpaid interest to the redemption date, starting one month, one month, three months, three months, and six months, respectively, before their maturity dates. Prior to these dates, ONEOK Partners may redeem these notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective note plus accrued and unpaid interest to the redemption date.

ONEOK Partners Debt Guarantee - ONEOK Partners’ senior notes are guaranteed fully and unconditionally on a senior unsecured basis by the Intermediate Partnership. The Intermediate Partnership’s guarantee is full and unconditional, subject to certain customary automatic release provisions. The guarantee ranks equally in right of payment to all of the Intermediate Partnership’s existing and future unsecured senior indebtedness. ONEOK Partners, L.P. has no significant assets or operations other than its investment in the Intermediate Partnership, which is also consolidated. At December 31, 2016, the Intermediate Partnership held the equity of ONEOK Partners’ subsidiaries, as well as a 50 percent interest in Northern Border Pipeline. ONEOK Partners’ long-term debt is nonrecourse to ONEOK.

Neither ONEOK nor ONEOK Partners guarantees the debt or other similar commitments of unaffiliated parties. ONEOK does not guarantee the debt or other similar commitments of ONEOK Partners, and ONEOK Partners does not guarantee the debt or other similar commitments of ONEOK. Following the completion of the Merger Transaction with ONEOK Partners, we and ONEOK Partners expect to enter into a cross guarantee agreement whereby each party to the agreement unconditionally guarantees and becomes liable for the indebtedness of each other party to the agreement.

Guardian Pipeline Senior Notes - These senior notes were issued under a master shelf agreement dated November 8, 2001, with certain financial institutions. Principal payments are due quarterly through 2022. Guardian Pipeline’s senior notes contain financial covenants that require the maintenance of certain financial ratios as defined in the master shelf agreement based on Guardian Pipeline’s financial position and results of operations. Upon any breach of these covenants, all amounts outstanding under the master shelf agreement may become due and payable immediately. At December 31, 2016,2019, Guardian Pipeline was in compliance with its financial covenants.


Other - We amortize premiums, discounts and expenses incurred in connection with the issuance of long-term debt consistent with the terms of the respective debt instrument.

Debt Guarantees - ONEOK, ONEOK Partners and the Intermediate Partnership have cross guarantees in place for our and ONEOK Partners’ indebtedness.


H.G.EQUITY


Noncontrolling Interests - As a result of the Merger Transaction in 2017, we and our subsidiaries own 100% of ONEOK Partners. The earnings of ONEOK Partners that are attributed to its units held by the public until June 30, 2017, are reported as “Net income attributable to noncontrolling interest” in our accompanying Consolidated Statements of Income. ONEOK Partners’ cash distributions paid prior to the Merger Transaction are reported as “Distributions to noncontrolling interests” in our accompanying Consolidated Statements of Changes in Equity.

In July 2018, we acquired the remaining 20% interest in WTLPG for $195 million with cash on hand. We are now the sole owner of the West Texas LPG pipeline system.

Series A and B Convertible Preferred Stock- There are no0 shares of Series A or Series B Preferred Stock currently issued or outstanding.


CommonSeries E Preferred Stock- At December 31, 2016,In April 2017, through a wholly owned subsidiary, we had approximately 373.2contributed 20,000 shares of newly issued Series E Preferred Stock, having an aggregate value of $20 million, to the Foundation for use in charitable and nonprofit causes. The contribution was recorded as a $20 million noncash expense in 2017, which represents a noncash financing activity, and is included in other expense in our Consolidated Statements of Income.

Equity Issuances - In January 2018, we completed an underwritten public offering of 21.9 million shares of authorized and unreservedour common stock availableat a public offering price of $54.50 per share, generating net proceeds of $1.2 billion. We used the net proceeds from this offering to fund capital expenditures and for issuance.general corporate purposes, which included repaying a portion of our outstanding indebtedness.


In July 2017, we established an “at-the-market” equity program for the offer and sale from time to time of our common stock up to an aggregate amount of $1 billion. The program allows us to offer and sell our common stock at prices we deem appropriate through a sales agent. Sales of our common stock may be made by means of ordinary brokers’ transactions on the NYSE, in block transactions, or as otherwise agreed to between us and the sales agent. We are under no obligation to offer and sell common stock under the program. NaN shares were sold through our “at-the-market” equity program in 2019 or 2018.

During the year ended December 31, 2017, we sold 8.4 million shares of common stock through our “at-the-market” equity program that resulted in net proceeds of $448.3 million. The net proceeds from these issuances were used for general corporate purposes, including repayment of outstanding indebtedness and to fund capital expenditures.

Dividends - Holders of our common stock share equally in any dividend declared by our Board of Directors, subject to the rights of the holders of outstanding preferred stock. Dividends paid totaled $517.6 million, $509.2 million$1.5 billion, $1.3 billion and $443.8$829.4 million for 2016, 20152019, 2018 and 2014,2017, respectively. In addition to the increase in dividends paid per share outlined in the table below, dividends paid increased due to the increase in number of shares outstanding as a result of the closing of the Merger Transaction and our equity issuances. The following table sets forth the quarterly dividends per share declared and paid on our common stock forin the periods indicated:
  Years Ended December 31,
  2019 2018 2017
First Quarter $0.860
 $0.770
 $0.615
Second Quarter 0.865
 0.795
 0.615
Third Quarter 0.890
 0.825
 0.745
Fourth Quarter 0.915
 0.855
 0.745
Total $3.53
 $3.245
 $2.72

  Years Ended December 31,
  2016 2015 2014
First Quarter $0.615
 $0.605
 $0.40
Second Quarter 0.615
 0.605
 0.56
Third Quarter 0.615
 0.605
 0.575
Fourth Quarter 0.615
 0.615
 0.59
Total $2.46
 $2.43
 $2.125


Additionally, in February 2020, we paid a quarterly dividend of $0.615$0.935 per share ($3.74 per share on an annualized basis), which was paid to shareholders of record as of January 27, 2020.

The Series E Preferred Stock pays quarterly dividends on each share of Series E Preferred Stock, when, as and if declared by our Board of Directors, at a rate of 5.5% per year. We paid dividends for the Series E Preferred Stock of $1.1 million in January 2017, payableboth 2019 and 2018 and $0.6 million in 2017. We paid quarterly dividends totaling $0.3 million for the first quarter 2017.Series E Preferred Stock in February 2020.



See Note O for a discussion of ONEOK Partners’ issuance of common units and distributions to noncontrolling interests.

I.H.ACCUMULATED OTHER COMPREHENSIVE LOSS


The following table sets forth the balance in accumulated other comprehensive loss for the periods indicated:
 
Unrealized Gains
(Losses) on
Risk-Management
Assets/Liabilities (a)
 
Unrealized
Holding Gains
(Losses)
on Investment
Securities (a)
 
Pension and
Postretirement
Benefit Plan
Obligations (a) (b)
 
Unrealized Gains
(Losses) on Risk-
Management
Assets/Liabilities of
Unconsolidated
Affiliates (a)
 
Accumulated
Other
Comprehensive
Loss (a)
 
(Thousands of dollars)
January 1, 2015$(37,349) $955
 $(99,959) $
 $(136,353)
Other comprehensive income (loss)
before reclassifications
10,444
 (955) 5,722
 (500) 14,711
Amounts reclassified from accumulated
other comprehensive loss
(15,294) 
 9,694
 
 (5,600)
Other comprehensive income
(loss) attributable to ONEOK
(4,850) (955) 15,416
 (500) 9,111
December 31, 2015(42,199) 
 (84,543) (500) (127,242)
Other comprehensive income (loss)
before reclassifications
(9,280) 
 (22,903) (475) (32,658)
Amounts reclassified from accumulated
other comprehensive loss
(676) 
 6,210
 16
 5,550
Other comprehensive income
(loss) attributable to ONEOK
(9,956) 
 (16,693) (459) (27,108)
December 31, 2016$(52,155) $
 $(101,236) $(959) $(154,350)
  
Risk-
Management
Assets/Liabilities (a)
 
Retirement and Other
Postretirement
Benefit Plan
Obligations (a) (b)
 
Risk-
Management
Assets/Liabilities of
Unconsolidated
Affiliates (a)
 
Accumulated
Other
Comprehensive
Loss (a)
  
(Thousands of dollars)
January 1, 2018 $(81,915) $(105,411) $(1,204) $(188,530)
Beginning balance adjustments (c) 3,078
 (805) (2,273) 
Other comprehensive income (loss) before reclassifications (5,673) (8,116) 2,396
 (11,393)
Amounts reclassified to net income 36,870
 12,887
 28
 49,785
Other comprehensive income (loss) attributable to ONEOK 31,197
 4,771
 2,424
 38,392
Impact of adoption of ASU 2018-02 (d) (17,020) (20,340) (741) (38,101)
December 31, 2018 (64,660) (121,785) (1,794) (188,239)
Other comprehensive loss before reclassifications (147,803) (19,490) (7,275) (174,568)
Amounts reclassified to net income (21,057) 9,794
 70
 (11,193)
Other comprehensive income (loss) (168,860) (9,696) (7,205) (185,761)
December 31, 2019 $(233,520) $(131,481) $(8,999) $(374,000)
(a) All amounts are presented net of tax.
(b) Includes amounts related to supplemental executive retirement plan.

(c) Reclassifications were made between categories to conform to current presentation.
(d) We elected to adopt this guidance in the first quarter 2018, which allows a reclassification from accumulated other comprehensive income/loss to retained earnings for the stranded tax effects resulting from the Tax Cuts and Jobs Act. After adopting and applying this guidance, our accumulated other comprehensive loss balance does not include stranded taxes resulting from the Tax Cuts and Jobs Act.

The following table sets forth information about the balance of accumulated other comprehensive loss at December 31, 2019, representing unrealized gains (losses) related to risk-management assets and liabilities:
(b) - Based on December 31, 2019, commodity prices, we will realize $28.9 million in net gains, net of tax, over the next 12 months and $0.8 million in net loss, net of tax, thereafter.
(c) - Losses of $20.3 million, net of tax, will be reclassified into earnings during the next 12 months as the hedged items affect earnings.

The remaining amounts in accumulated other comprehensive loss relate primarily to our retirement and other postretirement benefit plan obligations, which are expected to be amortized over the average remaining service period of employees participating in these plans.


The following table sets forth the effect of reclassifications from accumulated other comprehensive loss on our Consolidated Statements of Incometo net income for the periods indicated:
Details about Accumulated Other
Comprehensive Loss Components
 Years Ended December 31, 
Affected Line Item in the
Consolidated Statements of Income
2019 2018 2017
  
(Thousands of dollars)
  
Risk-management assets/liabilities        
Commodity contracts $50,345
 $(29,596) $(69,561) Commodity sales revenues/ cost of sales and fuel
Interest-rate contracts (23,230) (18,287) (21,025) Interest expense
  27,115
 (47,883) (90,586) Income before income taxes
  (6,058) 11,013
 26,899
 Income taxes
  21,057
 (36,870) (63,687) Net income
Noncontrolling interests 
 
 (18,146) Less: Net income attributable noncontrolling interests
  $21,057
 $(36,870) $(45,541) Net income attributable to ONEOK
         
Retirement and other postretirement benefit plan obligations (a)        
Amortization of net loss $(12,946) $(18,398) $(15,265) Other income (expense)
Amortization of unrecognized prior service credit 227
 1,662
 1,662
 Other income (expense)
  (12,719) (16,736) (13,603) Income before income taxes
  2,925
 3,849
 5,441
 Income taxes
  $(9,794) $(12,887) $(8,162) Net income attributable to ONEOK
         
Risk-management assets/liabilities of unconsolidated affiliates   

 

  
Interest-rate contracts $(91) $(36) $(367) Equity in net earnings from investments
  21
 8
 97
 Income taxes
  (70) (28) (270) Net income
Noncontrolling interests 
 
 (106) Less: Net income attributable to noncontrolling interests
  $(70) $(28) $(164) Net income attributable to ONEOK
         
Total reclassifications for the period attributable to ONEOK $11,193
 $(49,785) $(53,867) Net income attributable to ONEOK

Details about Accumulated Other
Comprehensive Loss Components
 Years Ended December 31, 
Affected Line Item
in the Consolidated
Statements of Income
2016 2015 2014
  
(Thousands of dollars)
  
Unrealized gains (losses) on risk-management assets/liabilities        
Commodity contracts $26,422
 $81,089
 $(21,052) Commodity sales revenues
Interest-rate contracts (19,215) (17,565) (21,966) Interest expense
  7,207
 63,524
 (43,018) Income before income taxes
  (230) (8,815) 8,977
 Income tax expense
  6,977
 54,709
 (34,041) Income from continuing operations
  
 
 (7,682) 
Income (loss) from discontinued
operations
  6,977
 54,709
 (41,723) Net income
Noncontrolling interest 6,301
 39,415
 (19,679) 
Less: Net income attributable to
noncontrolling interest
  $676
 $15,294
 $(22,044) Net income attributable to ONEOK
         
Pension and postretirement benefit plan obligations (a)        
Amortization of net loss $(12,012) $(17,724) $(15,914)  
Amortization of unrecognized prior service cost 1,662
 1,568
 1,469
  
  (10,350) (16,156) (14,445) Income before income taxes
  4,140
 6,462
 5,778
 Income tax expense
  (6,210) (9,694) (8,667) Income from continuing operations
  
 
 (1,648) Income (loss) from discontinued operations
  $(6,210) $(9,694) $(10,315) Net income attributable to ONEOK
         
Unrealized Gains (Losses) on Risk-Management Assets/Liabilities of Unconsolidated Affiliates        
  $(63) $
 $
 Equity in net earnings from investments
  10
 
 
 Income tax expense
  (53) 
 
 Net income
Noncontrolling interest (37) 
 
 Less: Net income attributable to noncontrolling interests
  $(16) $
 $
 Net income attributable to ONEOK
         
Total reclassifications for the period attributable to ONEOK $(5,550) $5,600
 $(32,359) Net income attributable to ONEOK
(a) - These components of accumulated other comprehensive loss are included in the computation of net periodic benefit cost. See Note LK for additional detail of our net periodic benefit cost.



J.I.EARNINGS PER SHARE


The following tables set forth the computation of basic and diluted EPS from continuing operations for the periods indicated:
  Year Ended December 31, 2016
  Income Shares 
Per Share
Amount
  
(Thousands, except per share amounts)
Basic EPS from continuing operations      
Income from continuing operations attributable to ONEOK available for common stock $354,090
 211,128
 $1.68
Diluted EPS from continuing operations  
  
  
Effect of dilutive securities 
 1,255
  
Income from continuing operations attributable to ONEOK available for common stock and common stock equivalents $354,090
 212,383
 $1.67
  Year Ended December 31, 2019
  Income Shares 
Per Share
Amount
  
(Thousands, except per share amounts)
Basic EPS      
Net income available for common stock $1,277,477
 413,560
 $3.09
Diluted EPS      
Effect of dilutive securities 
 1,884
  
Net income available for common stock and common stock equivalents $1,277,477
 415,444
 $3.07

  Year Ended December 31, 2015
  Income Shares 
Per Share
Amount
  
(Thousands, except per share amounts)
Basic EPS from continuing operations      
Income from continuing operations attributable to ONEOK available for common stock $251,058
 210,208
 $1.19
Diluted EPS from continuing operations  
  
  
Effect of dilutive securities ��
 333
  
Income from continuing operations attributable to ONEOK available for common stock and common stock equivalents $251,058
 210,541
 $1.19
  Year Ended December 31, 2018
  Income Shares 
Per Share
Amount
  
(Thousands, except per share amounts)
Basic EPS      
Net income attributable to ONEOK available for common stock $1,150,603
 411,485
 $2.80
Diluted EPS      
Effect of dilutive securities 
 2,710
  
Net income attributable to ONEOK available for common stock and common stock equivalents $1,150,603
 414,195
 $2.78
  Year Ended December 31, 2017
  Income Shares 
Per Share
Amount
  
(Thousands, except per share amounts)
Basic EPS      
Net income attributable to ONEOK available for common stock $387,074
 297,477
 $1.30
Diluted EPS      
Effect of dilutive securities 
 2,303
  
Net income attributable to ONEOK available for common stock and common stock equivalents $387,074
 299,780
 $1.29

  Year Ended December 31, 2014
  Income Shares 
Per Share
Amount
  
(Thousands, except per share amounts)
Basic EPS from continuing operations      
Income from continuing operations attributable to ONEOK available for common stock $319,714
 209,391
 $1.53
Diluted EPS from continuing operations  
  
  
Effect of dilutive securities 
 1,036
  
Income from continuing operations attributable to ONEOK available for common stock and common stock equivalents $319,714
 210,427
 $1.52


K.J.SHARE-BASED PAYMENTS


The ONEOK, Inc. Equity Compensation Plan (ECP) and the ONEOK, Inc. Long-Term Incentive Plan (LTIP) providehistorically provided for the granting of stock-based compensation, including incentive stock options, nonstatutory stock options, stock bonus awards, restricted stock awards, restricted stock-unitstock unit awards, performance stock awards and performance-unitperformance unit awards to eligible employees and the granting of stock awards to nonemployee directors. The ECP was terminated immediately following the issuance of new awards in February 2018. The awards issued prior to the termination remain subject to the terms of the ECP and the applicable award agreement. Similarly, the LTIP was terminated in May 2018, and the awards issued under the LTIP prior to the termination date remain subject to the terms of the LTIP and the applicable award agreement. In May 2018, our shareholders approved the ONEOK, Inc. Equity Incentive Plan (EIP), which has been used for all new equity awards since such date. We have reserved 10.0 million and 15.68.5 million shares of common stock for issuance under the ECPEIP and LTIP, respectively. Atat December 31, 2016,2019, we had approximately 2.4 million and 0.27.6 million shares available for issuance under the ECP and LTIP, respectively, which reflectplan. This calculation of available shares reflects shares issued and estimated shares expected to be issued upon vesting of outstanding awards granted under these plans, less forfeitures. These plans allow for the deferral of awards granted in stock or cash, in accordance with Internal Revenue Code section 409A requirements.EIP, excluding estimated forfeitures expected to be returned to the plan.


Restricted Stock Units - We have granted restricted stock units to key employees that vest overat the end of a three-year period and entitle the grantee to receive shares of our common stock. Restricted stock unit awards are measured at fair value as if they were vested and issued on the grant date reduced by expected dividend payments and adjusted for estimated forfeitures. Restricted stock unit awards granted accrue dividend equivalents in the form of additional restricted stock units prior to vesting. Compensation expense is recognized on a straight-line basis over the vesting period of the award.



Performance-UnitPerformance Unit Awards -We have granted performance-unitperformance unit awards to key employees. The shares of our common stock underlying the performance unitsemployees that vest at the expiration of a period determined by the Executive Compensation Committee if certain performance criteria are met by the company. Outstanding performance units vest at the expirationend of a three-year period. Upon vesting, a holder of outstanding performance units is entitled to receive a number of shares of our common stock equal to a percentage (0 percent(0% to 200 percent)200%) of the performance units granted, based on our total shareholder return over the vesting period, compared with the total shareholder return of a peer group of other energy companies over the same period. Compensation expense is recognized on a straight-line basis over the period of the award.

If paid, the outstanding performance unit awards entitle the grantee to receive the grant in shares of our common stock. Our outstanding performancePerformance unit awards are equity awards with a market-based condition, which results in the compensation cost for these awards being recognized over the requisite service period, provided that the requisite service period is fulfilled, regardless of when, if ever, the market condition is satisfied. Themeasured at fair value of these performance units was estimated on the grant date based on a Monte Carlo model.model and adjusted for estimated forfeitures. Performance stock unit awards granted accrue dividend equivalents in the form of additional performance units prior to vesting. The compensationCompensation expense is recognized on these awards only will be adjusted for changes in forfeitures.a straight-line basis over the vesting period of the award.


Stock Compensation Plan for Non-Employee Directors


The ONEOK, Inc. Stock Compensation Plan for Non-Employee Directors (the DSCP) providesand the LTIP historically provided for the granting of nonstatutory stock options, stock bonus awards, including performance-unit awards, restricted stockperformance unit awards and restricted stock unit awards. The DSCP was terminated in May 2018 and replaced by the EIP. Under the DSCP, theseEIP, awards may be granted by the Executive Compensation Committee at any time, until grants have been made for all shares authorized under the DSCP. We have reserved a total of 1.4 million shares of common stock for issuance under the DSCP, and at December 31, 2016, we had approximately 1.0 million shares available for issuance under the plan.EIP. The maximum

number of shares of common stock and cash-based awards that can be issued to a participant under the DSCPEIP during any year is 40,000.limited to $0.8 million in value as of the grant date. No performance unit awards, restricted stock unit awards or restricted stock awards have been made to nonemployee directors under the EIP, LTIP or DSCP. There are 0 options outstanding under the EIP, LTIP or DSCP.


General


For all awards outstanding, we used a 3 percent3% forfeiture rate based on historical forfeitures under our share-based payment plans. We currently use treasury stock to satisfy our share-based payment obligations.


Compensation cost expensedexpense for our share-based payment plans described above was $30.7$46.5 million, $11.5$33.2 million and $19.5$27.7 million during 2016, 20152019, 2018 and 2014,2017, respectively, which is net ofbefore related tax benefits of $9.8$31.7 million, $4.9$12.2 million and $6.8$11.1 million, respectively. Compensation cost expensed included in income from continuing operations for each respective year was $30.7 million, $11.5 million, and $16.8 million, net of tax benefits.


Restricted Stock Unit Activity


As of December 31, 2016,2019, we had $11.0$15.4 million of total unrecognized compensation cost related to our nonvested restricted stock unit awards, which is expected to be recognized over a weighted-average period of 1.8 years. The following tables set forth activity and various statistics for our restricted stock unit awards:
 
Number of
Units
 
Weighted
Average Price
 
Number of
Units
 
Weighted
Average Price
Nonvested December 31, 2015 463,569
 $45.88
Nonvested December 31, 2018 1,025,193
 $34.68
Granted 552,876
 $20.04
 262,399
 $58.07
Released to participants (124,075) $35.69
 (541,871) $19.73
Forfeited (10,723) $34.38
 (46,731) $49.61
Nonvested December 31, 2016 881,647
 $31.25
Nonvested December 31, 2019 698,990
 $54.05
  2019 2018 2017
Weighted-average grant date fair value (per share) $58.07
 $46.94
 $45.11
Fair value of units granted (thousands of dollars) $15,238
 $13,907
 $12,685
Grant date fair value of units vested (thousands of dollars) $10,691
 $9,552
 $7,258

  2016 2015 2014
Weighted-average grant date fair value (per share) $20.04
 $42.98
 $58.23
Fair value of units granted (thousands of dollars) $11,081
 $10,186
 $8,463
Fair value of units vested (thousands of dollars) $4,429
 $6,458
 $10,649



Performance-UnitPerformance Unit Activity


As of December 31, 2016,2019, we had $15.0$23.5 million of total unrecognized compensation cost related to the nonvested performance-unitperformance unit awards, which is expected to be recognized over a weighted-average period of 1.8 years. The following tables set forth activity and various statistics related to the performance-unitperformance unit awards and the assumptions used in the valuations of the 2016, 2015 and 2014 grants at the respective grant date:dates:
 
Number of
Units
 
Weighted
Average Price
 
Number of
Units
 
Weighted
Average Price
Nonvested December 31, 2015 691,260
 $51.01
Nonvested December 31, 2018 1,243,643
 $44.08
Granted 596,278
 $25.54
 338,427
 $68.02
Released to participants 
 $
 (636,628) $23.59
Forfeited (281,787) $40.66
 (7,621) $39.54
Nonvested December 31, 2016 1,005,751
 $38.81
Nonvested December 31, 2019 937,821
 $66.67
  2016 2015 2014
Volatility (a) 39.94% 26.70% 25.48%
Dividend Yield 11.32% 5.02% 2.63%
Risk-free Interest Rate 0.93% 1.00% 0.69%
  2019 2018 2017
Volatility (a) 27.10% 39.20% 40.59%
Dividend yield 5.05% 5.49% 4.68%
Risk-free interest rate 2.47% 2.44% 1.49%
(a) - Volatility was based on historical volatility over three years using daily stock price observations.
  2019 2018 2017
Weighted-average grant date fair value (per share) $68.02
 $59.57
 $56.65
Fair value of units granted (thousands of dollars) $23,020
 $22,081
 $17,621
Grant date fair value of units vested (thousands of dollars) $15,018
 $12,545
 $8,704

  2016 2015 2014
Weighted-average grant date fair value (per share) $25.54
 $50.30
 $64.75
Fair value of units granted (thousands of dollars) $15,229
 $13,370
 $12,071
Fair value of units vested (thousands of dollars) $
 $13,736
 $25,795


Employee Stock Purchase Plan


We have reserved a total of 11.6 million shares of common stock for issuance under our ONEOK, Inc. Employee Stock Purchase Plan (the ESPP). Subject to certain exclusions, all full-time employees are eligible to participate in the ESPP. Employees can choose to have up to 10 percent10% of their annual base pay withheld from each paycheck during the offering period to purchase our common stock, subject to terms and limitations of the plan. The purchase price of the stock is 85 percent85% of the lower of its grant date or exercise date market price. Approximately 57 percent, 53 percent62%, 60% and 67 percent58% of employees participated in the plan in 2016, 20152019, 2018 and 2014,2017, respectively. Under the plan, we sold 232,553171,590 shares at $27.21$51.24 per share in 2016, 222,8722019, 165,877 shares at $25.51$45.53 per share in 20152018 and 110,592151,803 shares at $43.85$44.20 per share in 2014.2017.


Employee Stock Award Program


Under our Employee Stock Award Program, we issued, for no monetary consideration, to all eligible employees one share of our common stock when the per-share closing price of our common stock on the NYSE was for the first time at or above $13 per share, and one additional share of common stock when the per-share closing price of our common stock on the NYSE was at or above each one dollar increment above $13. The total number of shares of our common stock available for issuance under this program is 900,000. Shares issued to employees under this program during 2019 and 2018 totaled 14,022 and 2,553, respectively. Compensation expense related to the Employee Stock Award Program was 900,000.$1.0 million and $0.2 million for 2019 and 2018, respectively. No shares were issued to employees under this program during 20162017. As of the date of this report, the next award will be issued when our common stock closes at or 2015. Shares issued to employees under this program during 2014 totaled 49,864 and compensation expense related to the Employee Stock Award Program was $2.1 million in 2014.above $78.


Deferred Compensation Plan for Non-Employee Directors


The ONEOK, Inc. Nonqualified Deferred Compensation Plan for Non-Employee Directors provides our nonemployee directors the option to defer all or a portion of their compensation for their service on our Board of Directors. Under the plan, directors may elect either a cash deferral option or a phantom stock option. Under the cash deferral option, directors may elect to defer the receipt of all or a portion of their annual retainer fees, plus accrued interest.which will be credited with interest during the deferral period. Under the phantom stock option, directors may defer all or a portion of their annual retainer fees and receive such fees on a deferred basis in the form of shares of common stock under our Long-Term Incentive Plan or Equity Compensation Plan.EIP, which earn the equivalent of dividends declared on our common stock. Shares are distributed to nonemployee directors at the fair market value of our common stock at the date of distribution.



L.K.EMPLOYEE BENEFIT PLANS


Retirement and Other Postretirement Benefit Plans


Retirement Plans - We have a defined benefit pension plan covering certain employees and former employees hired beforeprior to January 1, 2005. Employees hired after December 31, 2004, and employees who accepted a one-time opportunity to opt out of our defined benefit pension plan arehistorically were covered by our Profit Sharing Plan.Plan, which was merged into our 401(k) Plan as of December 31, 2018. In addition, we have a supplemental executive retirement plan for the benefit of certain officers. No new participants in our supplemental executive retirement plan have been approved since 2005, and effective January 2014, the plan was formally closed to new participants. We fund our pensionretirement costs at a level needed to maintain or exceed the minimum funding levels required by the Employee Retirement Income Security Act of 1974, as amended, and the Pension Protection Act of 2006.


Other Postretirement Benefit Plans - We sponsor health and welfare plans that provide postretirement medical and life insurance benefits to employees hired prior to 2017 who retire with at least five years of full-time service. The postretirement medical plan for pre-Medicare participants is contributory with retiree contributions adjusted periodically and contains other cost-sharing features such as deductibles and coinsurance. The postretirement medical plan for Medicare-eligible participants is an account-based plan under which participants may elect to purchase private insurance policies under a private exchange and/or seek reimbursement of other eligible medical expenses.


Obligations and Funded Status - The following tables settable sets forth our pensionretirement and other postretirement benefit plans benefit obligations and fair value of plan assets for our continuing operations for the periods indicated:
  Retirement Benefits Other Postretirement Benefits
  December 31, December 31,
  2019 2018 2019 2018
Change in benefit obligation 
(Thousands of dollars)
Benefit obligation, beginning of period $466,994
 $481,615
 $46,840
 $57,938
Service cost 7,825
 7,339
 468
 845
Interest cost 20,528
 17,659
 2,038
 2,108
Plan participants’ contributions 
 
 1,142
 1,050
Actuarial loss (gain) 55,954
 (24,345) 5,101
 (10,233)
Benefits paid (16,452) (15,274) (3,280) (4,868)
Benefit obligation, end of period 534,849
 466,994
 52,309
 46,840
         
Change in plan assets  
    
  
Fair value of plan assets, beginning of period 290,684
 306,008
 30,800
 34,133
Actual return on plan assets 58,060
 (12,350) 8,087
 (998)
Employer contributions 14,500
 12,300
 2,000
 1,100
Plan participants’ contributions 
 
 1,142
 1,050
Benefits paid (16,452) (15,274) (2,969) (4,485)
Fair value of plan assets, end of period 346,792
 290,684
 39,060
 30,800
Balance at December 31 $(188,057) $(176,310) $(13,249) $(16,040)
         
Current liabilities $(4,616) $(4,514) $
 $
Noncurrent liabilities (183,441) (171,796) (13,249) (16,040)
Balance at December 31 $(188,057) $(176,310) $(13,249) $(16,040)

  Pension Benefits Postretirement Benefits
  December 31, December 31,
  2016 2015 2016 2015
Change in benefit obligation 
(Thousands of dollars)
Benefit obligation, beginning of period $390,688
 $414,181
 $49,496
 $56,663
Service cost 6,501
 7,565
 596
 743
Interest cost 19,820
 18,218
 2,404
 2,347
Plan participants’ contributions 
 
 894
 1,005
Actuarial loss (gain) 24,458
 (34,826) 4,905
 (6,473)
Benefits paid (13,081) (12,574) (3,472) (4,433)
Other adjustments 
 (1,876) 
 (356)
Benefit obligation, end of period 428,386
 390,688
 54,823
 49,496
         
Change in plan assets  
  
  
  
Fair value of plan assets, beginning of period 258,635
 277,568
 28,641
 29,429
Actual return on plan assets 16,117
 (4,266) 1,902
 174
Employer contributions 
 
 1,000
 2,000
Plan participants’ contributions 
 
 894
 1,005
Benefits paid (13,081) (12,574) (2,887) (3,728)
Other adjustments 
 (2,093) 
 (239)
Fair value of plan assets, end of period 261,671
 258,635
 29,550
 28,641
Balance at December 31 $(166,715) $(132,053) $(25,273) $(20,855)
         
Current liabilities $(4,363) $(4,616) $
 $
Noncurrent liabilities (162,352) (127,437) (25,273) (20,855)
Balance at December 31 $(166,715) $(132,053) $(25,273) $(20,855)


The table above includes the supplemental executive retirement plan obligation. ONEOK has investments included in other assets on the Consolidated Balance Sheets, which totaled $84.5$98.9 million and $81.1$87.7 million at December 31, 20162019 and 2015,2018, respectively, for the purpose of funding the obligation. These assets are excluded from the table above as those are not assets of the supplemental executive retirement plan.plan and are excluded from the table above.


The accumulated benefit obligation for our pensionretirement plans for our continuing operations was $407.2$498.8 million and $370.8$434.4 million at December 31, 20162019 and 2015,2018, respectively.


The actuarial gains and losses impacting our benefit obligations for our retirement and other postretirement benefit plans are due primarily to changes in the discount rate assumptions discussed in the “Actuarial Assumptions” section below.


Components of Net Periodic Benefit Cost -The following table sets forth the components of net periodic benefit cost for our pensionretirement and other postretirement benefit plans for our continuing operations for the periods indicated:
  Retirement Benefits Other Postretirement Benefits
  Years Ended December 31, Years Ended December 31,
  2019 2018 2017 2019 2018 2017
  
(Thousands of dollars)
Components of net periodic benefit cost            
Service cost $7,825
 $7,339
 $6,896
 $468
 $845
 $662
Interest cost 20,528
 17,659
 18,645
 2,038
 2,108
 2,261
Expected return on plan assets (23,600) (23,917) (21,376) (2,285) (2,690) (2,257)
Amortization of prior service credit 
 
 
 (227) (1,662) (1,662)
Amortization of net loss 12,649
 17,060
 13,586
 297
 1,338
 1,679
Net periodic benefit cost $17,402
 $18,141
 $17,751
 $291
 $(61) $683

  Pension Benefits Postretirement Benefits
  Years Ended December 31, Years Ended December 31,
  2016 2015 2014 2016 2015 2014
  
(Thousands of dollars)
Components of net periodic benefit cost            
Service cost $6,501
 $7,565
 $7,238
 $596
 $743
 $710
Interest cost 19,820
 18,218
 18,324
 2,404
 2,347
 2,433
Expected return on plan assets (20,348) (20,900) (19,526) (2,124) (2,253) (2,163)
Amortization of prior service cost (credit) 
 94
 193
 (1,662) (1,662) (1,662)
Amortization of net loss 10,966
 15,981
 15,078
 1,046
 1,743
 836
Net periodic benefit cost $16,939
 $20,958
 $21,307
 $260
 $918
 $154


Other Comprehensive Income (Loss) - The following table sets forth the amounts recognized in other comprehensive income (loss) related to our pension benefitsretirement and other postretirement benefits for our continuing operations for the periods indicated:
  Retirement Benefits Other Postretirement Benefits
  Years Ended December 31, Years Ended December 31,
  2019 2018 2017 2019 2018 2017
  
(Thousands of dollars)
Net gain (loss) $(25,389) $(16,351) $(16,572) $700
 $6,545
 $(328)
Prior service cost (601) 
 
 
 
 
Amortization of prior service credit 
 
 
 (227) (1,662) (1,662)
Amortization of net loss 12,649
 17,060
 13,586
 297
 1,338
 1,679
Deferred income taxes (a) 3,068
 (18,928) (960) (177) (2,831) 82
Total recognized in other comprehensive income (loss) $(10,273) $(18,219) $(3,946) $593
 $3,390
 $(229)

  Pension Benefits Postretirement Benefits
  Years Ended December 31, Years Ended December 31,
  2016 2015 2014 2016 2015 2014
  
(Thousands of dollars)
Net gain (loss) arising during the period $(33,043) $5,145
 $(49,293) $(5,128) $4,393
 $(7,220)
Amortization of prior service cost (credit) 
 94
 193
 (1,662) (1,662) (1,662)
Amortization of net loss 10,966
 15,981
 15,078
 1,046
 1,743
 836
Deferred income taxes 8,831
 (8,488) 13,609
 2,297
 (1,790) 3,218
Total recognized in other comprehensive income (loss) $(13,246) $12,732
 $(20,413) $(3,447) $2,684
 $(4,828)
(a) - Year ended December 31, 2018, includes the impact of adopting ASU 2018-02, “Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.”


The table below sets forth the amounts in accumulated other comprehensive loss that had not yet been recognized as components of net periodic benefit expense for our continuing operations for the periods indicated:
  Retirement Benefits Other Postretirement Benefits
  December 31, December 31,
  2019 2018 2019 2018
  
(Thousands of dollars)
Prior service credit (cost) $(601) $
 $
 $227
Accumulated loss (172,952) (160,212) (4,110) (5,108)
Accumulated other comprehensive loss (173,553) (160,212) (4,110) (4,881)
Deferred income taxes 46,354
 43,286
 1,389
 1,567
Accumulated other comprehensive loss, net of tax $(127,199) $(116,926) $(2,721) $(3,314)

  Pension Benefits Postretirement Benefits
  December 31, December 31,
  2016 2015 2016 2015
  
(Thousands of dollars)
Prior service credit (cost) $
 $
 $3,550
 $5,212
Accumulated loss (157,935) (135,858) (14,341) (10,259)
Accumulated other comprehensive loss (157,935) (135,858) (10,791) (5,047)
Deferred income taxes 63,174
 54,343
 4,316
 2,019
Accumulated other comprehensive loss, net of tax $(94,761)
$(81,515)
$(6,475)
$(3,028)


The following table sets forth the amounts recognized in accumulated comprehensive loss expected to be recognized as components of net periodic benefit expense for our continuing operations in the next fiscal year.
  
Pension
Benefits
 
Postretirement
Benefits
Amounts to be recognized in 2017 
(Thousands of dollars)
Prior service (credit) cost $
 $(1,662)
Net loss $13,586
 $1,679


Actuarial Assumptions - The following table sets forth the weighted-average assumptions used to determine benefit obligations for pensionretirement and other postretirement benefits for the periods indicated:
 Pension Benefits Postretirement Benefits Retirement Benefits Other Postretirement Benefits
 December 31, December 31, December 31, December 31,
 2016 2015 2016 2015 2019 2018 2019 2018
Discount rate 4.50% 5.25% 4.25% 5.00% 3.50% 4.50% 3.50% 4.50%
Compensation increase rate 3.10% 3.10% N/A N/A 3.70% 3.65% NA NA


The following table sets forth the weighted-average assumptions used to determine net periodic benefit costs for the periods indicated:
  Years Ended December 31,
  2019 2018 2017
Discount rate - retirement plans 4.50% 3.75% 4.50%
Discount rate - other postretirement plans 4.50% 3.75% 4.25%
Expected long-term return on plan assets 7.50% 8.00% 7.75%
Compensation increase rate 3.65% 3.00% 3.10%

  Years Ended December 31,
  2016 2015 2014
Discount rate - pension plans 5.25% 4.50% 5.25%
Discount rate - postretirement plans 5.00% 4.25% 5.00%
Expected long-term return on plan assets 7.75% 8.00% 7.75%
Compensation increase rate 3.10% 3.15% 3.20%


We determine our overall expected long-term rate of return on plan assets based on our review of historical returns and economic growth models.


We determine our discount rates annually. We estimate our discount rate based upon a comparisonannually utilizing portfolios of high quality bonds matched to the expectedestimated benefit cash flows associated withof our future payments under our pensionretirement and other postretirement obligations to a hypothetical bond portfolio created using high-quality bonds that closely match expected cash flows. Bond portfolios are developed by selecting a bond for each of the next 60 years based on the maturity dates of the bonds.benefit plans. Bonds selected to be included in the portfolios are only those rated by S&P or Moody’s as AA-an AA or Aa2 rating or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.


Health Care Cost Trend Rates -The following table sets forth the assumed health care cost-trend rates for the periods indicated:
  2019 2018
Health care cost-trend rate assumed for next year 7.00% 6.50%
Rate to which the cost-trend rate is assumed to decline
(the ultimate trend rate)
 5.00% 5.00%
Year that the rate reaches the ultimate trend rate 2024 2022

  2016 2015
Health care cost-trend rate assumed for next year 7.25% 4.0% - 7.50%
Rate to which the cost-trend rate is assumed to decline
(the ultimate trend rate)
 5.00% 4.0% - 5.0%
Year that the rate reaches the ultimate trend rate 2022 2022


Assumed health care cost-trend rates have an impact on the amounts reported for our health care plans. A one percentage point change in assumed health care cost-trend rates would have the following effects on our continuing operations:
  
One Percentage
Point Increase
 
One Percentage
Point Decrease
  
(Thousands of dollars)
Effect on total of service and interest cost $63
 $(57)
Effect on postretirement benefit obligation $994
 $(907)


Plan Assets -Our investment strategy is to invest plan assets in accordance with sound investment practices that emphasize long-term fundamentals. The goal of this strategy is to maximize investment returns while managing risk in order to meet the plan’s current and projected financial obligations. The investment policy for our defined benefit pension plan follows a glide path approach toward liability-driven investing that shifts a higher portfolio weighting to fixed income as the plan'splan’s funded status increases. The purpose of liability-driven investing is to structure the asset portfolio to more closely resemble the pension liability and thereby more effectively hedge against changes in the liability. The plan’s current investments include a diverse blend of various domestic and international equities, investments in various classes of debt securities, insurance contractsreal estate and venture capital.hedge funds. The target allocation for the assets of our pensionretirement plan as of December 31, 2016,2019, is as follows:
U.S. large-capDomestic and international equities 3742%
Long duration bondsfixed income 30%
Developed foreign large-cap equitiesReturn-seeking credit11%
Hedge funds 10%
Alternative investmentsReal estate funds 8%
Mid-cap equities6%
Emerging markets equities5%
Small-cap equities47%
Total 100%


As part of our risk management for the plans, minimums and maximums have been set for each of the asset classes listed above. All investment managers for the plan are subject to certain restrictions on the securities they purchase and, with the exception of indexing purposes, are prohibited from owning our stock.


The following tables set forth our pension benefits and postretirement benefitsthe plan assets by fair value category for our continuing operations as of the measurement date:date for our defined benefit pension and other postretirement benefit plans:
 Pension Benefits Pension Benefits
 December 31, 2016 December 31, 2019
Asset Category Level 1 Level 2 Level 3 Subtotal 
Measured at NAV (d)
 Total Level 1 Level 2 Level 3 Subtotal 
Measured at NAV (d)
 Total
 
(Thousands of dollars)
 
(Thousands of dollars)
Investments:                        
Equity securities (a) $146,980
 $13,606
 $
 $160,586
 $
 $160,586
 $47
 $
 $
 $47
 $149,985
 $150,032
Real estate funds 
 
 
 
 23,885
 23,885
Government obligations 
 17,979
 
 17,979
 
 17,979
 
 
 
 
 50,708
 50,708
Corporate obligations (b) 
 56,484
 
 56,484
 
 56,484
 
 
 
 
 85,898
 85,898
Common/collective trusts 
 6,577
 
 6,577
 
 6,577
 
 3,263
 
 3,263
 
 3,263
Cash 43
 
 
 43
 
 43
 63
 
 
 63
 
 63
Other investments (c) 
 
 
 
 20,002
 20,002
 
 
 
 
 32,943
 32,943
Fair value of plan assets $147,023
 $94,646
 $
 $241,669
 $20,002
 $261,671
 $110
 $3,263
 $
 $3,373
 $343,419
 $346,792
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category represents alternative investments in limited partnerships, which can be redeemed with a 30-day notice with no further restrictions. There are 0unfunded capital commitments.
(d) - Plan asset investments measured at fair value using the net asset value per share.


  Pension Benefits
  December 31, 2018
Asset Category Level 1 Level 2 Level 3 Subtotal 
Measured at NAV (d)
 Total
  
(Thousands of dollars)
Investments:            
Equity securities (a) $58
 $
 $
 $58
 $116,790
 $116,848
Real estate funds 
 
 
 
 20,569
 20,569
Government obligations 
 
 
 
 48,913
 48,913
Corporate obligations (b) 
 
 
 
 69,377
 69,377
Common/collective trusts 
 3,961
 
 3,961
 
 3,961
Cash 95
 
 
 95
 
 95
Other investments (c) 
 
 
 
 30,921
 30,921
Fair value of plan assets $153
 $3,961
 $
 $4,114
 $286,570
 $290,684
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category represents alternative investments in limited partnerships, which can be redeemed with a 30-day notice with no further restrictions. There are no0 unfunded capital commitments.
(d) - Plan asset investments measured at fair value using the net asset value per share.

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  Pension Benefits
  December 31, 2015
Asset Category Level 1 Level 2 Level 3 Subtotal 
Measured at NAV (d)
 Total
  
(Thousands of dollars)
Investments:            
Equity securities (a) $143,515
 $13,517
 $
 $157,032
 $
 $157,032
Government obligations 
 20,241
 
 20,241
 
 20,241
Corporate obligations (b) 
 55,495
 
 55,495
 
 55,495
Common/collective trusts 
 5,076
 
 5,076
 
 5,076
Cash 525
 
 
 525
 
 525
Other investments (c) 
 
 
 
 20,266
 20,266
Fair value of plan assets $144,040
 $94,329
 $
 $238,369
 $20,266
 $258,635
  Other Postretirement Benefits
  December 31, 2019
Asset Category Level 1 Level 2 Level 3 Total
  
(Thousands of dollars)
Investments:        
Equity securities (a) $2,043
 $
 $
 $2,043
Money market funds 
 2,428
 
 2,428
Insurance and group annuity contracts 
 34,589
 
 34,589
Fair value of plan assets $2,043
 $37,017
 $
 $39,060
(a) - This category represents securities of the respective market sector from diverse industries.
(b) - This category represents bonds from diverse industries.
(c) - This category represents alternative investments in limited partnerships, which can be redeemed with a 30-day notice with no further restrictions.
(d) - Plan asset investments measured at fair value using the net asset value per share.


 Postretirement Benefits Other Postretirement Benefits
 December 31, 2016 December 31, 2018
Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total
 
(Thousands of dollars)
 
(Thousands of dollars)
Investments:                
Equity securities (a) $1,777
 $
 $
 $1,777
 $1,792
 $
 $
 $1,792
Money market funds 
 1,259
 
 1,259
 1
 413
 
 414
Insurance and group annuity contracts 
 26,514
 
 26,514
 
 28,594
 
 28,594
Fair value of plan assets $1,777
 $27,773
 $
 $29,550
 $1,793
 $29,007
 $
 $30,800
(a) - This category represents securities of the respective market sector from diverse industries.


  Postretirement Benefits
  December 31, 2015
Asset Category Level 1 Level 2 Level 3 Total
  
(Thousands of dollars)
Investments:        
Equity securities (a) $1,632
 $
 $
 $1,632
Money market funds 
 1,398
 
 1,398
Insurance and group annuity contracts 
 25,611
 
 25,611
Fair value of plan assets $1,632
 $27,009
 $
 $28,641
(a)Contributions - This category represents securities of the respective market sector from diverse industries.

Contributions -During 2016,2019, we made no$14.5 million in contributions to our defined benefit pension plan and $1.0$2.0 million in contributions to our other postretirement benefit plans. We contributed $7.5$12.1 million to our defined benefit pension plan in January 20172020 and expect to make approximately $2.0 million in contributions to our other postretirement plans in 2017.the remainder of 2020.


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Pension and Other Postretirement Benefit Payments - Benefit payments for our defined benefit pension and other postretirement benefit plans for the period ending December 31, 2016,2019, were $13.1$16.5 million and $3.5$3.3 million, respectively. The following table sets forth the defined benefit pension benefits and other postretirement benefits payments expected to be paid in 20172020 through 2026:2029:
  
Pension
Benefits
 
Other Postretirement
Benefits
Benefits to be paid in: 
(Thousands of dollars)
2020 $18,277
 $3,422
2021 $19,252
 $3,399
2022 $20,202
 $3,519
2023 $21,170
 $3,454
2024 $22,228
 $3,446
2025 through 2029 $123,959
 $16,385

  
Pension
Benefits
 
Postretirement
Benefits
Benefits to be paid in: 
(Thousands of dollars)
2017 $15,487
 $3,251
2018 $16,717
 $3,436
2019 $17,788
 $3,616
2020 $18,672
 $3,801
2021 $19,839
 $3,900
2022 through 2026 $111,899
 $19,326


The expected benefits to be paid are based on the same assumptions used to measure our benefit obligation at December 31, 2016,2019, and include estimated future employee service.


Other Employee Benefit Plans


401(k) Plan - We have a 401(k) Plan covering all employees, and employee contributions are discretionary. We historically maintained a profit-sharing plan for all employees hired after December 31, 2004, which was merged into our 401(k) Plan as of December 31, 2018, and ceased to exist as a separate plan. We match 100 percent100% of employee 401(k) contributions up to 6 percent6% of each participant’s eligible compensation, subject to certain limits.limits, and generally make a quarterly profit sharing contribution equal to 1% of each profit-sharing participant’s eligible compensation during the quarter and an annual discretionary profit-sharing contribution. Our contributions made to the plan, for our continuing operationsincluding profit-sharing contributions, were $11.9$30.4 million, $12.0$28 million and $9.3$21.1 million in 2016, 20152019, 2018 and 2014,2017, respectively.


Profit Sharing Plan - We have a profit-sharing plan (Profit Sharing Plan) for all employees hired after December 31, 2004. Employees who were employed prior to January 1, 2005, were given a one-time opportunity to make an irrevocable election to participate in the Profit Sharing Plan and not accrue any additional benefits under our defined benefit pension plan after December 31, 2004. We plan to make a contribution to the Profit Sharing Plan each quarter equal to 1 percent of each participant’s eligible compensation during the quarter. Additional discretionary employer contributions may be made at the end of each year. Employee contributions are not allowed under the plan. Our contributions made to the plan for our continuing operations were $8.2 million, $4.9 million and $4.6 million in 2016, 2015 and 2014, respectively.

Nonqualified Deferred Compensation Plan -The 2019 Nonqualified Deferred Compensation Plan providesand its predecessor nonqualified deferred compensation plans (collectively, the NQDC Plan) provide select employees, as approved by our Chief Executive Officer, with the option to defer portions of their compensation and providesprovide nonqualified deferred compensation benefits that are not available due to limitations on employer and employee contributions to qualified defined contribution plans under the federal tax laws. The NQDC Plan also provides benefits in excess of applicable tax limits for certain participants in the defined benefit pension plan who are not participants in the supplemental executive retirement plan. Our contributions to the plan were not material in 2016, 20152019, 2018 and 2014.2017.


M.L.INCOME TAXES


The following table sets forth our provisionsprovision for income taxes for the periods indicated:
  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars)
Current tax expense (benefit)      
Federal $(1,278) $260
 $295
State 963
 1,633
 1,670
Total current tax expense (benefit) (315) 1,893
 1,965
Deferred tax expense      
Federal 327,806
 319,551

376,728
State 44,923
 41,459
 68,589
Total deferred tax expense 372,729
 361,010
 445,317
Total provision for income taxes $372,414
 $362,903
 $447,282

  Years Ended December 31,
  2016 2015 2014
Current income taxes 
(Thousands of dollars)
Federal $6,086
 $13,191
 $10,180
State 2,449
 2,967
 3,311
Total current income taxes from continuing operations 8,535
 16,158
 13,491
Deferred income taxes  
  
  
Federal 193,974
 116,681
 152,352
State 9,897
 3,761
 (14,685)
Total deferred income taxes from continuing operations 203,871
 120,442
 137,667
Total provision for income taxes from continuing operations 212,406
 136,600
 151,158
Discontinued operations (1,250) 2,031
 7,567
Total provision for income taxes $211,156
 $138,631
 $158,725

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The following table is a reconciliation of our income tax provision from continuing operations for the periods indicated:
  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars)
Income before income taxes $1,650,991
 $1,517,935
 $1,040,801
Less: Net income attributable to noncontrolling interests 
 3,329
 205,678
Net income attributable to ONEOK before income taxes 1,650,991
 1,514,606
 835,123
Federal statutory income tax rate 21.0% 21.0% 35.0%
Provision for federal income taxes 346,708
 318,067
 292,293
State income taxes, net of federal benefit 34,545
 38,668
 16,197
Deferred tax rate change, inclusive of valuation allowance 11,340
 5,552
 141,283
Excess tax benefits from share-based compensation (20,983) (4,644) 
Other, net 804
 5,260
 (2,491)
Income tax provision $372,414
 $362,903
 $447,282

  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars)
Income from continuing operations before income taxes $957,956
 $521,876
 $819,873
Less: Net income attributable to noncontrolling interest 391,460
 134,218
 349,001
Income from continuing operations attributable to ONEOK before income taxes 566,496
 387,658
 470,872
Federal statutory income tax rate 35% 35% 35%
Provision for federal income taxes 198,274
 135,680
 164,805
State income taxes, net of federal tax benefit 12,303
 5,800
 14,278
State deferred tax rate change, net of valuation allowance 43
 928
 (25,653)
Other, net 1,786
 (5,808) (2,272)
Income tax provision from continuing operations $212,406
 $136,600
 $151,158


The following table sets forth the tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities for the periods indicated:
 December 31,
2016
 December 31,
2015
 December 31,
2019
 December 31,
2018
Deferred tax assets 
(Thousands of dollars)
 
(Thousands of dollars)
Employee benefits and other accrued liabilities $118,831
 $97,719
 $99,510
 $91,587
Federal net operating loss 26,334
 76,805
 858,030
 420,318
State net operating loss and benefits 39,759
 39,363
 171,779
 108,004
Derivative instruments 32,082
 26,132
 83,710
 22,108
Other 2,425
 12,386
 12,769
 13,378
Total deferred tax assets 219,431
 252,405
 1,225,798
 655,395
Valuation allowance for state tax credits    
Valuation allowance for state net operating loss and tax credits    
Carryforward expected to expire prior to utilization (9,430) (10,223) (94,794) (73,820)
Net deferred tax assets 210,001
 242,182
 1,131,004
 581,575
Deferred tax liabilities        
Excess of tax over book depreciation 107,249
 93,421
 84,631
 73,113
Investment in partnerships(a) 1,726,541
 1,585,427
 1,582,436
 728,193
Regulatory assets 33
 49
Total deferred tax liabilities 1,833,823
 1,678,897
 1,667,067
 801,306
Net deferred tax liabilities before discontinued operations 1,623,822
 1,436,715
Discontinued operations (10,500) (18,265)
Net deferred tax liabilities $1,613,322
 $1,418,450
Net deferred tax assets (liabilities) $(536,063) $(219,731)

(a) Due primarily to excess of tax over book depreciation.

In December 2017, the Tax Cuts and Jobs Act was signed into law. The Tax Cuts and Jobs Act made extensive changes to the U.S. tax laws and included provisions that, beginning in 2018, reduced the U.S. corporate tax rate to 21% from 35%, increased expensing for capital investment, limited the interest deduction, and limited the use of net operating losses to offset future taxable income. We revalued our deferred tax assets and liabilities as required at enactment. At that time, our net deferred tax assets represented expected corporate tax benefits in the future. The reduction in the federal corporate tax rate reduced these benefits, which resulted in a one-time noncash charge to net income through income tax expense of $141.3 million, inclusive of the valuation allowance described below, recorded in the fourth quarter 2017.

Tax benefits related to certain state net operating loss, (NOL)tax credit carryforwards and charitable contribution carryforwards will begin expiring in 2030. We2020. Due to the Tax Cuts and Jobs Act and the impact of increased expensing for capital investment, we believe that it is more likely than not that the tax benefits of the net operating losscertain carryforwards will not be utilized prior to their expirations; therefore, no valuation allowance is necessary.

Deferred tax assets related to tax benefits of employee share-based compensation have been reduced for performance share units and restricted share units that vested in periods in which ONEOK was in an NOL position. This vesting resulted in tax deductions in excess of previously recorded benefits based on the performance share unit and restricted share unit value at the time of grant. Although these additional tax benefits are reflected in NOL carryforwards in the tax return, the additional tax benefit is not recognized until the deduction reduces taxes payable. A portion of the tax benefit does not reduce ONEOK’s current taxes payable due to NOL carryforwards; accordingly, these tax benefits are not reflected in ONEOK’s NOLs in deferred tax assets. Cumulative tax benefits included in NOL carryforwards but not reflected in deferred tax assets were $73.4 million as of December 31, 2016, and $75.1 million as of December 31, 2015. As a result of adopting ASU 2016-09 in 2017, the portion of the tax benefit that does not reduce ONEOK’s current taxes payable will be reflected in deferred tax assets. See Note A for more information on ASU 2016-09.

ONE Gas Separation - ONE Gas was included in our consolidated federal and state income tax returns through the date of the separation. Any changes to the estimated ONE Gas taxes at the separation date will result in a reimbursement between us and
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ONE Gas under the terms of the tax sharing agreement. We are principally responsible for managing any income tax audits by the various tax jurisdictions for periods prior to the separation.

Deferred tax liabilities and deferred income tax expense were reduced by $34.6 million in the first quarter 2014 due primarily to a reduction in our estimate of the effective state income tax rate to reflect a change in the mix of taxable income in the states in which we now operate, resulting from the separation of our former natural gas distribution business and the wind down of our energy services business. We also recorded a valuation allowance of $8.2$11.3 million, $5.6 million and $54.1 million through net income related to these tax benefits in the first quarter 2014 for state tax credits as it is more likely than not that we will not be able to utilize these credits as a result of the separation of our former natural gas distribution business2019, 2018 and the wind down of our energy services business. Together, these adjustments resulted in a net $26.4 million reduction in deferred tax liabilities and deferred income tax expense.2017, respectively.


N.M.UNCONSOLIDATED AFFILIATES


Investments in Unconsolidated Affiliates - The following table sets forth ONEOK Partners’our investments in unconsolidated affiliates for the periods indicated:
  
Net
Ownership
Interest
 December 31,
2019
 December 31,
2018
    
(Thousands of dollars)
Northern Border Pipeline 50% $307,209
 $381,623
Overland Pass Pipeline 50% 417,473
 429,295
Roadrunner 50% 80,816
 93,857
Other Various 56,346
 64,375
Investments in unconsolidated affiliates (a) $861,844
 $969,150
  
Net
Ownership
Interest
 December 31,
2016
 December 31,
2015
    
(Thousands of dollars)
Northern Border Pipeline 50% $328,456
 $363,231
Overland Pass Pipeline Company 50% 444,138
 459,354
Other Various 186,213
 125,636
Investments in unconsolidated affiliates (a)   $958,807
 $948,221

(a) - Equity-method goodwill (Note A) was $40.1$38.8 million at December 31, 20162019 and 2015, respectively.2018.


Equity in Net Earnings from Investments and Impairments -The following table sets forth ONEOK Partners’our equity in net earnings from investments for the periods indicated:
  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars)
Northern Border Pipeline $68,871
 $67,854
 $68,153
Overland Pass Pipeline 63,698
 65,887
 60,067
Roadrunner 26,839
 22,993
 19,150
Other (4,867) 1,649
 11,908
Equity in net earnings from investments $154,541
 $158,383
 $159,278
Impairment of equity investments $
 $
 $(4,270)

  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars)
Northern Border Pipeline $69,990
 $66,941
 $69,819
Overland Pass Pipeline Company 53,984
 37,783
 25,906
Other 15,716
 20,576
 21,690
Equity in net earnings from investments $139,690
 $125,300
 $117,415
Impairment of equity investments $
 $(180,583) $(76,412)


Impairment Charges - In 2017, following a review of nonstrategic assets for potential divestiture, we recorded $4.3 million of noncash impairment charges related to a nonstrategic equity investment located in Oklahoma, which was later sold.

Unconsolidated Affiliates Financial Information - The following tables set forth summarized combined financial information of ONEOK Partners’our unconsolidated affiliates for the periods indicated:
  December 31,
2016
 December 31,
2015
  
(Thousands of dollars)
Balance Sheet    
Current assets $143,317
 $149,439
Property, plant and equipment, net $2,579,607
 $2,556,559
Other noncurrent assets $20,784
 $23,722
Current liabilities $77,388
 $211,037
Long-term debt $649,539
 $425,521
Other noncurrent liabilities $69,265
 $69,356
Accumulated other comprehensive loss $(7,450) $(5,669)
Owners’ equity $1,954,966
 $2,029,475
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  December 31,
2019
 December 31,
2018
  
(Thousands of dollars)
Balance Sheet    
Current assets $149,564
 $158,723
Property, plant and equipment, net $2,314,631
 $2,413,662
Other noncurrent assets $13,252
 $16,273
Current liabilities $88,142
 $83,057
Long-term debt $581,327
 $480,731
Other noncurrent liabilities $76,685
 $47,826
Accumulated other comprehensive income (loss) $(28,373) $2,053
Owners’ equity $1,759,666
 $1,974,991

  Years Ended December 31,
  2019 2018 2017
  
(Thousands of dollars)
Income Statement      
Revenues $634,135
 $637,762
 $639,102
Operating expenses $291,210
 $276,373
 $277,121
Net income $315,274
 $337,694
 $347,692
       
Distributions paid to us (a) $257,644
 $197,285
 $196,114
  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars)
Income Statement      
Operating revenues $578,542
 $524,496
 $548,491
Operating expenses (a) $260,753
 $304,930
 $309,990
Net income (a) $293,921
 $200,064
 $214,410
       
Distributions paid to us $196,717
 $155,918
 $139,019

(a) Includes long-lived asset impairment charges in 2015 and 2014.As determined by the Northern Border Pipeline Management Committee, we received an additional distribution of $50.0 million from Northern Border Pipeline during the year ended December 31, 2019.


ONEOK Partners’We incurred expenses in transactions with unconsolidated affiliates of $140.3$164.7 million, $104.7$153.9 million and $62.0$156.1 million for 2016, 20152019, 2018 and 2014,2017, respectively, primarily related to Overland Pass Pipeline Company and Northern Border Pipeline. Accounts payable to ONEOK Partners’our equity-method investees at December 31, 20162019 and 2015, was $11.12018, were $13.5 million and $8.0$14.7 million, respectively.


Northern Border Pipeline- The Northern Border Pipeline partnership agreement provides that distributions to Northern Border Pipeline’s partners are to be made on a pro rata basis according to each partner’s percentage interest. The Northern Border Pipeline Management Committee determines the amount and timing of such distributions. Any changes to, or suspension of, the cash distribution policy of Northern Border Pipeline requires the unanimous approval of the Northern Border Pipeline Management Committee. Cash distributions are equal to 100 percent100% of distributable cash flow as determined from Northern Border Pipeline’s financial statements based upon EBITDA less interest expense and maintenance capital expenditures. Loans or other advances from Northern Border Pipeline to its partners or affiliates are prohibited under its credit agreement. In 2019 and 2018, we made 0 contributions to Northern Border Pipeline. In 2017, we made equity contributions of $83 million to Northern Border Pipeline.


Northern Border Pipeline entered into a settlement with shippers that was approved by the FERC in February 2018. The settlement provides for tiered rate reductions beginning January 1, 2018, that reduced tariff rates 12.5% by January 2020, compared with previous tariff rates and requires new rates to be established by January 2024. We do not expect the impact of lower tariff rates on Northern Border Pipeline’s earnings and cash distributions to be material to us.

Overland Pass Pipeline Company- The Overland Pass Pipeline Company limited liability company agreement provides that distributions to Overland Pass Pipeline Company’sPipeline’s members are to be made on a pro rata basis according to each member’s percentage interest. The Overland Pass Pipeline Company Management Committee determines the amount and timing of such distributions. Any changes to, or suspension of, the cash distributions from Overland Pass Pipeline Company requires the unanimous approval of the Overland Pass Pipeline Company Management Committee. Cash distributions are equal to 100 percent100% of available cash as defined in the limited liability company agreement.


Roadrunner Gas Transmission- In March 2015, ONEOK Partners entered into a 50-50 joint venture with a subsidiary of Fermaca, a Mexico City-based natural gas infrastructure company, to construct the Roadrunner pipeline to transport natural gas from the Permian Basin in West Texas to the Mexican border near El Paso, Texas. ONEOK Partners contributed approximately $65 million and $30 million to Roadrunner in 2016 and 2015, respectively.

The Roadrunner limited liability agreement provides that distributions to members are made on a pro rata basis according to each member’s ownership interest. TheAs the operator, we have been delegated the authority to determine such distributions in accordance with, and on the frequency set forth in, the Roadrunner Management Committee determines the amount and timing of such distributions.agreement. Cash distributions are equal to 100 percent100% of available cash, as defined in the limited liability company agreement. In 2019, 2018 and 2017, our contributions to Roadrunner were not material.

Impairment Charges - Due to the continued and greater than expected decline in volumes gathered in the dry natural gas area of the Powder River Basin, ONEOK Partners evaluated its long-lived assets and equity investments in this area in 2015 and made the decision to cease operations of its wholly owned coal-bed methane natural gas gathering system in 2016. Bighorn Gas Gathering, in which ONEOK Partners owns a 49 percent equity interest, and Fort Union Gas Gathering, in which ONEOK Partners owns a 37 percent equity interest, are both partially supplied with volumes from ONEOK Partners’ wholly owned coal-bed methane natural gas gathering system. ONEOK Partners owns a 35 percent equity interest in Lost Creek Gathering Company, which also is located in a dry natural gas area. ONEOK Partners reviewed its Bighorn Gas Gathering, Fort Union Gas Gathering and Lost Creek Gathering Company equity investments and recorded noncash impairment charges of $180.6 million in 2015. The remaining net book value of ONEOK Partners’ equity investments in this dry natural gas area is $31.1 million as of December 31, 2016.

In 2014, Bighorn Gas Gathering recorded an impairment of its underlying assets when the operator determined that the volume decline would be sustained for the foreseeable future. As a result, ONEOK Partners reviewed its equity investment in Bighorn Gas Gathering for impairment and recorded noncash impairment charges of $76.4 million in 2014.

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O.ONEOK PARTNERS

Ownership Interestin ONEOK Partners - Our ownership interest in ONEOK Partners is shown in the table below as of December 31, 2016:
General partner interest2.0%
Limited partner interest (a)39.2%
Total ownership interest41.2%
(a) - Represents 41.3 million common units and approximately 73.0 million Class B units, which are convertible, at our option, into common units.

Consolidation - We determined ONEOK Partners is a VIE due to the limited partners’ lack of substantive voting rights under the Partnership Agreement. Substantive voting rights under a master limited partnership are either kick-out rights or participating rights, as defined by FASB Accounting Standards Codification 810-10, that can be exercised with a simple majority of the vote of the limited partners. Prior to the adoption of ASU 2015-02, ONEOK Partners was not considered a VIE but was consolidated by us under the presumption that a general partner consolidates its limited partnership. See Note A for more information on ASU 2015-02.


We have determined that we are the primary beneficiary of ONEOK Partners as we have the power, through our general partner interest, to direct the operations of ONEOK Partners that impact its economic performance and the right to receive the benefits of ONEOK Partners through our general partner and limited partner interests. These interests are significant due to our 41.2 percent ownership interest in ONEOK Partners, the largest ownership interest by an individual entity, and our incentive distribution rights.

As we are the primary beneficiary of ONEOK Partners, we consolidate ONEOK Partners in our consolidated financial statements; however, we are restricted from the assets and cash flows of ONEOK Partners except for the distributions we receive from ONEOK Partners. Distributions are declared quarterly by the board of ONEOK Partners’ general partner based on the terms of the Partnership Agreement.

The following table shows the carrying amount and classification of ONEOK Partners’ assets and liabilities in our Consolidated Balance Sheets:
  December 31, December 31,
  2016 2015
  
(Thousands of dollars)
Assets    
Total current assets $1,174,245
 $883,164
Net property, plant and equipment 12,462,692
 12,256,791
Total investments and other assets 1,832,410
 1,787,631
Total assets $15,469,347
 $14,927,586
Liabilities    
Total current liabilities $2,824,376
 $1,580,300
Long-term debt, excluding current maturities 6,291,307
 6,695,312
Total deferred credits and other liabilities 175,844
 154,631
Total liabilities $9,291,527
 $8,430,243

ONEOK receives distributions from ONEOK Partners through its general partner and limited partner interests, but otherwise the assets of ONEOK Partners cannot be used to settle obligations of ONEOK. ONEOK does not guarantee the debt, commercial paper or other similar commitments of ONEOK Partners, and the obligations of ONEOK Partners may only be settled using the assets of ONEOK Partners. ONEOK Partners does not guarantee the debt or other similar commitments of ONEOK. Following the completion of the Merger Transaction with ONEOK Partners described in Note B, we and ONEOK Partners expect to enter into a cross guarantee agreement whereby each party to the agreement unconditionally guarantees and becomes liable for the indebtedness of each other party to the agreement.

Equity Issuances - ONEOK Partners has an “at-the-market” equity program for the offer and sale from time to time of its common units, up to an aggregate amount of $650 million. The program allows ONEOK Partners to offer and sell its common units at prices it deems appropriate through a sales agent. Sales of common units are made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between ONEOK Partners and the sales agent.
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ONEOK Partners is under no obligation to offer and sell common units under the program. At December 31, 2016, ONEOK Partners had approximately $138 million of registered common units available for issuance through its “at-the-market” equity program.

During the year ended December 31, 2016, ONEOK Partners sold no common units through its “at-the-market” equity program.

In August 2015, ONEOK Partners completed the sale to us in a private placement of 21.5 million common units at a price of $30.17 per unit. Additionally, ONEOK Partners completed a concurrent sale of approximately 3.3 million common units at a price of $30.17 per unit to funds managed by Kayne Anderson Capital Advisors in a registered direct offering, which were issued through ONEOK Partners’ existing “at-the-market” equity program. The combined offerings generated net cash proceeds of approximately $749 million to ONEOK Partners. In conjunction with these issuances, ONEOK Partners GP contributed approximately $15.3 million in order to maintain our 2 percent general partner interest in ONEOK Partners. ONEOK Partners used the proceeds for general partnership purposes, including capital expenditures and repayment of commercial paper borrowings.

During the year ended December 31, 2015, ONEOK Partners sold 10.5 million common units through its “at-the-market” equity program, including the units sold to funds managed by Kayne Anderson Capital Advisors in the offering discussed above. The net proceeds, including ONEOK Partners GP’s contribution to maintain our 2 percent general partner interest in ONEOK Partners, were approximately $381.6 million, which were used for general partnership purposes, including repayment of commercial paper borrowings.

In May 2014, ONEOK Partners completed an underwritten public offering of 13.9 million common units at a public offering price of $52.94 per common unit, generating net proceeds of approximately $714.5 million. In conjunction with this issuance, ONEOK Partners GP contributed approximately $15.0 million in order to maintain our 2 percent general partner interest in ONEOK Partners. ONEOK Partners used the proceeds for general partnership purposes, including capital expenditures and repayment commercial paper borrowings.

During the year ended December 31, 2014, ONEOK Partners sold 7.9 million common units through its “at-the-market” equity program. The net proceeds, including ONEOK Partners GP’s contribution to maintain our 2 percent general partner interest in ONEOK Partners, were approximately $402.1 million, which were used for general partnership purposes.

We account for the difference between the carrying amount of our investment in ONEOK Partners and the underlying book value arising from issuance of common units by ONEOK Partners as an equity transaction.  If ONEOK Partners issues common units at a price different than our carrying value per unit, we account for the premium or deficiency as an adjustment to paid-in capital. As a result of ONEOK Partners’ issuance of common units, we recognized a decrease to paid-in capital of approximately $34.4 million, net of taxes in 2015, and an increase to paid-in capital of approximately $156.1 million, net of taxes, in 2014.

Cash Distributions - We receive distributions from ONEOK Partners on our common and Class B units and our 2 percent general partner interest, which includes our incentive distribution rights. Under the Partnership Agreement, distributions are made to the partners with respect to each calendar quarter in an amount equal to 100 percent of available cash as defined in the Partnership Agreement. Available cash generally will be distributed 98 percent to limited partners and 2 percent to the general partner. The general partner’s percentage interest in quarterly distributions is increased after certain specified target levels are met during the quarter. Under the incentive distribution provisions, as set forth in the Partnership Agreement, the general partner receives:
15 percent of amounts distributed in excess of $0.3025 per unit;
25 percent of amounts distributed in excess of $0.3575 per unit; and
50 percent of amounts distributed in excess of $0.4675 per unit.

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The following table shows ONEOK Partners’ distributions paid during the periods indicated:
  Years Ended December 31,
  2016 2015 2014
  
(Thousands, except per unit amounts)
Distribution per unit $3.16
 $3.16
 $3.01
       
General partner distributions $26,640
 $24,610
 $21,044
Incentive distributions 402,152
 371,500
 304,999
Distributions to general partner 428,792
 396,110
 326,043
Limited partner distributions to ONEOK 361,292
 310,230
 279,292
Limited partner distributions to noncontrolling interest 541,919
 524,135
 446,910
Total distributions paid $1,332,003
 $1,230,475
 $1,052,245

ONEOK Partners’ distributions are declared and paid within 45 days of the end of each quarter. The following table shows ONEOK Partners’ distributions declared for the periods indicated:
  Years Ended December 31,
  2016 2015 2014
  
(Thousands, except per unit amounts)
Distribution per unit $3.16
 $3.16
 $3.07
       
General partner distributions $26,640
 $25,356
 $22,109
Incentive distributions 402,152
 382,759
 326,022
Distributions to general partner 428,792
 408,115
 348,131
Limited partner distributions to ONEOK 361,292
 327,250
 284,860
Limited partner distributions to noncontrolling interest 541,919
 532,405
 472,466
Total distributions declared $1,332,003
 $1,267,770
 $1,105,457

Affiliate Transactions - We provide a variety of services to our affiliates, including cash management and financial services, employee benefits, legal and administrative services by our employees and management, insurance and office space leased in our headquarters building and other field locations. Where costs are incurred specifically on behalf of an affiliate, the costs are billed directly to the affiliate by us. In other situations, the costs may be allocated to the affiliates through a variety of methods, depending upon the nature of the expenses and the activities of the affiliates. Beginning in the second quarter 2014, we allocate substantially all of our general overhead costs to ONEOK Partners as a result of the separation of our natural gas distribution business and the wind down of our energy services business in the first quarter 2014. For the first quarter 2014, it is not practicable to determine what these general overhead costs would be on a stand-alone basis.

The following table shows ONEOK Partners’ transactions with us for the periods indicated:
  Years Ended December 31,
  2016 2015 2014
  
(Thousands of dollars)
Revenues $
 $
 $53,526
       
Expenses  
  
  
Cost of sales and fuel $
 $
 $10,835
Operating expenses 388,142
 368,346
 330,541
Total expenses $388,142
 $368,346
 $341,376

Prior to the ONE Gas separation, ONEOK Partners provided natural gas sales and transportation and storage services to our former natural gas distribution business. Prior to February 1, 2014, these revenues and related costs were eliminated in consolidation. Beginning February 1, 2014, these revenues represent third-party transactions with ONE Gas and are not eliminated in consolidation, as such sales and services have continued subsequent to the separation and are expected to continue in future periods. Prior to the completion of the energy services wind down, ONEOK Partners provided natural gas and natural gas liquids sales and transportation and storage services to our energy services business. While these transactions
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were eliminated in consolidation in previous periods, they are now reflected as affiliate transactions and not eliminated in consolidation as these transactions have continued with third parties. See Note Q for additional detail on these revenues.

ONEOK Partners has an operating agreement with Roadrunner that provides for reimbursement or payment to itus for management services and certain operating costs. Charges toReimbursements and payments from Roadrunner included in operating income in our Consolidated Statements of Income for 2016the years ended December 31, 2019, 2018 and 20152017, were $7.7 million and $5.4 million, respectively.not material.


P.N.COMMITMENTS AND CONTINGENCIES


Commitments - Operating leases represent future minimum lease payments under noncancelable leases covering office space and pipeline equipment. Rental expense in 2016, 2015 and 2014 was not material. ONEOK and ONEOK Partners have no material operating leases. Firm transportation and storage contracts are fixed-price contracts that provide us with firm transportation and storage capacity. The following table sets forth ONEOK Partners’our firm transportation and storage contract payments for the periods indicated:
  
Firm
Transportation
and Storage
Contracts
  
(Millions of dollars)
2020 $61.6
2021 48.1
2022 40.1
2023 36.4
2024 34.3
Thereafter 177.9
Total $398.4

ONEOK Partners 
Firm
Transportation
and Storage
Contracts
  
(Millions of dollars)
2017 $51.5
2018 43.0
2019 37.5
2020 37.1
2021 23.0
Thereafter 35.0
Total $227.1


Environmental Matters and Pipeline Safety -The operation of pipelines, plants and other facilities for the gathering, processing, transportation and storage of natural gas, NGLs, condensate and other products is subject to numerous and complex laws and regulations pertaining to health, safety and the environment. As an owner and/or operator of these facilities, ONEOK Partnerswe must comply with United States laws and regulations at the federal, state and local levels that relate to air and water quality, hazardous and solid waste management and disposal, cultural resource protection and other environmental matters. The cost of planning, designing, constructing and operating pipelines, plants and other facilities must incorporate compliance with environmentalthese laws and regulations and safety standards. Failure to comply with these laws and regulations may trigger a variety of administrative, civil and potentially criminal enforcement measures, including citizen suits, which can include the assessment of monetary penalties, the imposition of remedial requirements and the issuance of injunctions or restrictions on operation.operation or construction. Management believes that, based on currently known information, compliance with these laws and regulations will not have a material adverse effect onaffect adversely our or ONEOK Partners’ results of operations, financial condition or cash flows.


Legal Proceedings - Gas Index Pricing Litigation - As previously reported, we and our affiliate, ONEOK and its subsidiary, OESC,Energy Services Company, L.P., along with several other energy companies, are defendingwere named as defendants in multiple lawsuits arising from alleged market manipulation or false reporting of natural gas prices to natural gas-index publications alleged to have occurred prior to 2003.


In November 2016,September 2019, we settled Sinclair Oil Corporation v. ONEOK Energy Services Company, L.P. (filed in the claims alleged against us and our affiliate OESC in Reorganized FLI. TheUnited States District Court for the District of Wyoming) for an immaterial amount we paid to settle this case is not material to our results of operations, financial position or cash flows and was paid with cash on hand.

In November 2016, we entered into an agreement to settle This was the claims alleged against us and our affiliates, OESC and Kansas Gas Marketing Company, in the following cases: Learjet,Arandell,Heartland and NewPage. The amount we agreed to pay to settle these cases is not material to our results of operations, financial position or cash flows and is expected to be paid with cash on hand.

The above settlements do not apply to the Sinclair case. We expect that future charges, if any,last remaining case arising from the ultimate resolution of this matter will not be material to our results of operations, financial position or cash flows and is expected to be paid with cash on hand.Gas Index Pricing Litigation.


Other Legal Proceedings-We and ONEOK Partners are a party to various other litigation matters and claims that have arisen in the normal course of our operations. While the results of these various other litigation matters and claims cannot be predicted
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with certainty, we believe the reasonably possible losses from such matters, individually and in the aggregate, are not material. Additionally, we believe the probable final outcome of such matters will not have a material adverse effect onaffect adversely our consolidated results of operations, financial position or cash flows.

O.LEASES

Adoption of ASC Topic 842: Leases -We adopted Topic 842 using the modified retrospective method and the optional transition method to record the adoption impact through a cumulative-effect adjustment to retained earnings as of January 1, 2019. Results for reporting periods beginning after January 1, 2019, are presented under Topic 842, while prior periods are not adjusted and continue to be reported under the accounting standards in effect for those periods.

Practical Expedients and Policies Elected - We applied the short-term policy election, which allows us to exclude from recognition leases with an initial term of 12 months or less. We elected the hindsight expedient, which allows us to use hindsight in assessing lease term; the package of practical expedients permitted under the guidance, which among other things, allows us to carry forward the historical lease classification; and the land easement expedient, which allows us to apply the guidance prospectively at adoption for land easements on existing agreements.

ONE Gas SeparationAdoption - In connection withAdoption of Topic 842 resulted in new operating lease assets and lease liabilities on our Consolidated Balance Sheet of $17.5 million and $17.4 million, respectively, as of January 1, 2019. The difference between the separationlease assets and lease liabilities was recorded as an adjustment to the beginning balance of ONE Gas,retained earnings, which represents the cumulative impact of adopting the standard. Our accounting for finance leases did not change. Adoption of Topic 842 did not materially impact our Consolidated Financial Statements.

Leases -We lease certain buildings, warehouses, office space, pipeline capacity, land and equipment, including pipeline equipment, rail cars, and information technology equipment. Our lease payments are generally straight-line and the exercise of lease renewal options, which vary in term, is at our sole discretion. We include renewal periods in a lease term if we entered intoare reasonably certain to exercise available renewal options. Our lease agreements do not include any residual value guarantees or material restrictive covenants.

Through ONEOK Leasing Company, L.L.C. and ONEOK Parking Company, L.L.C., we own an office building and a Separationparking garage and Distribution Agreement with ONE Gas, whichlease excess space in these facilities to affiliates and others. Our consolidated lease income is not material.

The following table sets forth supplemental information about our cash flows:
  Year Ended
  December 31, 2019
  
(Thousands of dollars)
Cash paid for amounts included in the measurement of lease liabilities  
Operating cash flows for operating leases $6,213
Financing cash flows for finance lease $1,764
Right-of-use assets obtained in exchange for operating lease liabilities (noncash) $4,097


The following table sets forth information about our lease assets and liabilities included in our Consolidated Balance Sheet for the period indicated:
LeasesLocation in our Consolidated Balance Sheet December 31, 2019
   
(Thousands of dollars)
Assets   
Operating leasesOther assets $15,147
Finance leaseProperty, plant and equipment 28,286
Finance leaseAccumulated depreciation (1,320)
Total leased assets  $42,113
    
Liabilities   
Current   
Operating leasesOther current liabilities $1,883
Finance leaseFinance lease liability 1,949
Noncurrent   
Operating leasesOther deferred credits 13,509
Finance leaseFinance lease liability 24,296
Total lease liabilities  $41,637



The following table sets forth information about our leases for the period indicated:
   Year Ended December 31, 2019At December 31, 2019
 
Location in our
Consolidated
Statement of Income
Lease Cost
Weighted-Average
Remaining
Lease Term
 
Weighted-Average
Discount
Rate (a)
   
(Thousands of dollars)
(Years)
  
Operating leasesOperations and maintenance $6,803
10.4 4.58%
Finance lease   8.8 10.00%
Amortization of lease assetsDepreciation and amortization 1,131
   
Interest on lease liabilitiesInterest expense 2,721
   
Total lease cost  $10,655
   
(a) - Our weighted-average discount rates represent the rate implicit in the lease or our incremental borrowing rate for a term equal to the remaining term of the lease.

The following table sets forth the agreements between usmaturity of our lease liabilities as of December 31, 2019:
  
Finance
Lease
 
Operating
Leases
  
(Millions of dollars)
2020 $4.5
 $2.5
2021 4.5
 2.1
2022 4.5
 2.0
2023 4.5
 1.9
2024 4.5
 1.9
2025 and beyond 17.1
 9.2
Total lease payments 39.6
 19.6
Less: Interest 13.4
 4.2
Present value of lease liabilities $26.2
 $15.4


Our future lease payments presented under the previous accounting standard as of December 31, 2018, are not materially different than those presented above.

As of December 31, 2019, we have entered into an additional operating lease that had not yet commenced with an estimated present value of $75.6 million and ONE Gas regarding the principal transactions necessary to effect the separation, including cross-indemnities between us and ONE Gas. In general, we agreed to indemnify ONE Gas for any liabilities relating toa lease term of 10 years, which is excluded from our business following the separation, including ONEOK Partnersmaturities table above and our energy services business,lease right-of-use assets and ONE Gas agreedliabilities.

P.REVENUES

Accounting Policies - See Note A for revenue recognition accounting policies.


Contract Assets and Contract Liabilities - The following tables set forth the changes in our contract asset and contract liability balances for the periods indicated:
Contract Assets 
(Millions of dollars)
Balance at January 1, 2018 (a) $6.4
Amounts invoiced in excess of revenue recognized (0.9)
Net additions 0.7
Balance at December 31, 2018 (b) 6.2
Amounts invoiced in excess of revenue recognized (1.7)
Net additions 0.5
Balance at December 31, 2019 (c) $5.0
(a) - Balance includes $0.9 million of current assets.
(b) - Contract assets of $1.7 million and $4.5 million are included in other current assets and other assets, respectively, in our Consolidated Balance Sheet.
(c) - Contract assets of $1.3 million and $3.7 million are included in other current assets and other assets, respectively, in our Consolidated Balance Sheet.
Contract Liabilities 
(Millions of dollars)
Balance at January 1, 2018 (a) $33.3
Revenue recognized included in beginning balance (19.5)
Net additions 17.9
Balance at December 31, 2018 (b) 31.7
Revenue recognized included in beginning balance (15.6)
Net additions 41.0
Balance at December 31, 2019 (c) $57.1
(a) - Balance includes $19.5 million of current liabilities.
(b) - Contract liabilities of $15.6 million and $16.1 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet.
(c) - Contract liabilities of $22.2 million and $34.9 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet.

In 2019, net additions for contract liabilities relate primarily to indemnify us for liabilities relating todeferred revenue on contributions in aid of construction received from customers and NGL storage contracts.

Receivables from Customers and Revenue Disaggregation - Substantially all of the natural gas distribution business. If a liability does notbalances in accounts receivable on our Consolidated Balance Sheets at December 31, 2019, and December 31, 2018, relate to either ourcustomer receivables. Revenues sources are disaggregated in Note Q.

Practical Expedients - We do not disclose the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) variable consideration on contracts for which we recognize revenue at the amount to which we have the right to invoice for services performed.

Transaction Price Allocated to Unsatisfied Performance Obligations - The following table presents aggregate value allocated to unsatisfied performance obligations as of December 31, 2019, and the amounts we expect to recognize in revenue in future periods, related primarily to firm transportation and storage contracts with remaining businesscontract terms ranging from one month to 24 years:
Expected Period of Recognition in Revenue 
(Millions of dollars)
2020 $343.5
2021 290.4
2022 214.8
2023 166.4
2024 and beyond 807.2
Total estimated transaction price allocated to unsatisfied performance obligations $1,822.3


The table above excludes variable consideration allocated entirely to wholly unsatisfied performance obligations, wholly unsatisfied promises to transfer distinct goods or services that are part of a single performance obligation and consideration we determine to ONE Gas, then webe fully constrained. Information on the nature of the variable consideration excluded and ONE Gas will each be responsible for a portionthe nature of such liability.the

performance obligations to which the variable consideration relates can be found in the description of the major contract types discussed in Note A. The amounts we determined to be fully constrained relate to future sales obligations under long-term sales contracts where the transaction price is not known and minimum volume agreements, which we consider to be fully constrained until invoiced.

Q.DISCONTINUED OPERATIONS

Separation of ONE Gas - On January 31, 2014, we completed the separation of ONE Gas. ONE Gas consists of our former natural gas distribution business. ONEOK shareholders of record at the close of business on January 21, 2014, retained their shares of ONEOK stock and received one share of ONE Gas stock for every four shares of ONEOK stock owned in a transaction that was tax-free to ONEOK and its shareholders. We retained no ownership interest in ONE Gas. Excluding cash of ONE Gas at separation, the separation was accounted for as a noncash activity.

Wind Down of Energy Services Business - On March 31, 2014, we completed the wind down of our energy services business. We executed agreements in 2013 and the first quarter 2014 to release a significant portion of our nonaffiliated natural gas transportation and storage contracts to third parties that resulted in noncash charges, which are included in income (loss) from discontinued operations, net of tax, in our Consolidated Statements of Income.

The following table summarizes the change in our liability related to released capacity contracts for the period indicated:
  Years Ended December 31,
  2016 2015
  
(Millions of dollars)
Beginning balance $36.3
 $73.8
Settlements (19.9) (38.5)
Accretion 0.5
 1.0
Ending balance $16.9
 $36.3

We expect future cash payments associated with released transportation and storage capacity from the wind down of our former energy services business to total approximately $18 million, which consists of approximately $10 million paid in 2017, $4 million in 2018, $1 million in 2019, and $3 million during the period from 2020 through 2023.

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Results of Operations of Discontinued Operations - The results of operations for our former natural gas distribution business and energy services business have been reported as discontinued operations for all periods presented. Income (loss) from discontinued operations, net of tax, in the Consolidated Statements of Income for the years ended December 31, 2016 and 2015, consists of accretion expense, net of tax benefit, on the released contracts for our former energy services business and certain tax-related adjustments. The table below provides selected financial information reported in discontinued operations in the Consolidated Statements of Income for the year ended December 31, 2014:
  Year Ended
  December 31, 2014
  
Natural Gas
Distribution
 
Energy
Services
 Total
  
(Thousands of dollars)
Revenues $287,249
 $353,404
 $640,653
Cost of sales and fuel (exclusive of items shown separately below) 190,893
 364,648
 555,541
Operating costs 60,847
(a)5,051
 65,898
Depreciation and amortization 11,035
 319
 11,354
Operating income (loss) 24,474
 (16,614) 7,860
Other income (expense), net (888) (7) (895)
Interest expense, net (4,592) (413) (5,005)
Income tax benefit (expense) (16,415) 8,848
 (7,567)
Income (loss) from discontinued operations, net $2,579
 $(8,186) $(5,607)
(a) - Includes approximately $23.0 million for the year ended December 31, 2014, of costs related to the ONE Gas separation.

Prior to the ONE Gas separation, natural gas sales and transportation and storage services provided to our former natural gas distribution business by ONEOK Partners were $7.5 million for the year ended December 31, 2014. Prior to February 1, 2014, these revenues and related costs were eliminated in consolidation. Beginning February 1, 2014, these revenues represent third-party transactions with ONE Gas and are not eliminated in consolidation for all periods presented, as such sales and services have continued subsequent to the separation and are expected to continue in future periods.

Prior to the completion of the energy services wind down, natural gas sales and transportation and storage services provided to our energy services business by ONEOK Partners were $46.0 million for the year ended December 31, 2014. While these transactions were eliminated in consolidation in previous periods, they are reflected now as affiliate transactions and are not eliminated in consolidation for all periods presented as these transactions have continued with third parties.

Statement of Financial Position of Discontinued Operations - At December 31, 2016 and 2015, assets and liabilities of discontinued operations in our Consolidated Balance Sheets relate primarily to deferred tax assets and capacity release obligations associated with our former energy services business.

R.    ACQUISITIONS

In November 2014, ONEOK Partners completed the acquisition of an 80 percent interest in WTLPG and a 100 percent interest in the Mesquite Pipeline for approximately $800 million from affiliates of Chevron Corporation, and ONEOK Partners became the operator of both pipelines. Financing to close this transaction came from available cash on hand and borrowings under its existing commercial paper program.

We accounted for the West Texas LPG acquisition as a business combination which, among other things, requires assets acquired and liabilities assumed to be measured at their acquisition-date fair values.

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The final purchase price allocation and assessment of the fair value of the assets acquired as of the acquisition date were as follows:
  
(Thousands of dollars)
Cash $13,839
Accounts receivable 9,132
Other current assets 3,369
Property, plant and equipment  
Regulated 812,716
Nonregulated 157,643
Total property, plant and equipment 970,359
Total fair value of assets acquired 996,699
   
Accounts payable (8,621)
Other liabilities (10,867)
Total fair value of liabilities acquired (19,488)
   
Less: Fair value of noncontrolling interest (162,438)
Net assets acquired 814,773
Less: Cash received (13,839)
Net cash paid for acquisition $800,934

Beginning November 29, 2014, the results of operations for West Texas LPG are included in the Natural Gas Liquids segment. We consolidate WTLPG and have recorded noncontrolling interests in consolidated subsidiaries on our Consolidated Statements of Income and Consolidated Balance Sheets to recognize the portion of WTLPG that ONEOK Partners does not own. The portion of the assets and liabilities of WTLPG acquired attributable to noncontrolling interests was accounted for as noncash activity. The fair value of the noncontrolling interest of WTLPG was estimated by applying a market approach.

Revenues and earnings related to West Texas LPG have been included within our Consolidated Statements of Income since the acquisition date. Supplemental pro forma revenue and earnings reflecting this acquisition as if it had occurred as of January 1, 2014, are not materially different from the information presented in the accompanying Consolidated Statements of Income and are, therefore, not presented.

The limited partnership agreement of WTLPG provides that cash distributions to the partners are to be made on a pro rata basis according to each partner’s ownership interest. Cash distributions are equal to 100 percent of distributable cash as defined in the limited partnership agreement of WTLPG. Any changes to, or suspension of, the cash distributions from WTLPG requires the approval of a minimum of 90 percent of the ownership interest and a minimum of two general partners of WTLPG.

S.SEGMENTS


Segment Descriptions - Our operations are divided into three reportable business segments, are based upon the following segments of ONEOK Partners:as follows:
theour Natural Gas Gathering and Processing segment gathers, treats and processes natural gas;
theour Natural Gas Liquids segment gathers, treats, fractionates and transports NGLs and stores, markets and distributes NGL products; and
theour Natural Gas Pipelines segment operates regulated interstate and intrastate natural gas transmission pipelines and natural gas storage facilities.


Other and eliminations consist of corporate costs, the operating and leasing operationsactivities of our headquarters building and related parking facility and other amounts neededeliminations necessary to reconcile our reportable segments to our consolidated financial statements.Consolidated Financial Statements.


Accounting Policies-The accounting policies of the segments are described in Note A. Our chief operating decision-maker reviews the financial performance of each of ONEOK Partners’ three segments, as well as our financial performance, on a regular basis. Beginning in 2016, adjusted EBITDA by segment is utilized in this evaluation. We believe this financial measure is useful to investors because it and similar measures are used by many companies in our industry as a measurement of financial performance and are commonly employed by financial analysts and others to evaluate our financial performance and to compare financial performance among companies in our industry. Adjusted EBITDA for each segment is defined as net
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income adjusted for interest expense, depreciation and amortization, noncash impairment charges, income taxes, allowance for equity funds used during construction and other noncash items. This calculation may not be comparable with similarly titled measures of other companies. Prior period segment disclosures have been recast to reflect this change.

Intersegment and affiliate sales are recorded on the same basis as sales to unaffiliated customers and are discussed further in Note O. Revenues from sales and services provided by ONEOK Partners to our former natural gas distribution business prior to the separation, which were previously eliminated in consolidation, are now reported as sales to affiliated customers for the year ended December 31, 2014, and are no longer eliminated in consolidation. Revenues from sales and services provided by ONEOK Partners to our former natural gas distribution business after the separation are reported as sales to unaffiliated customers as these now represent third-party transactions.

Customers - The primary customers of the Natural Gas Gathering and Processing segment are crude oil and natural gas producers, which include both large integrated and independent exploration and production companies. The Natural Gas Liquids segment’s customers are primarily NGL and natural gas gathering and processing companies; large integrated and independent crude oil and natural gas production companies; propane distributors; ethanol producers; and petrochemical, refining and NGL marketing companies. The Natural Gas Pipelines segment’s customers are primarily local natural gas distribution companies, electric-generation companies, large industrial companies, municipalities, irrigation customers and marketing companies.


For each of the years ended December 31, 2016, 20152019, 2018 and 2014, ONEOK Partners2017, we had no single customer from which itwe received 10 percent10% or more of our consolidated revenues.


Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated:
Year Ended December 31, 2016 Natural Gas
Gathering and
Processing
 Natural Gas
Liquids (a)
 Natural Gas
Pipelines (b)
 
Total
Segments
Year Ended December 31, 2019 
Natural Gas
Gathering and
Processing
 
Natural Gas
Liquids (a)
 
Natural Gas
Pipelines (b)
 
Total
Segments
 
(Thousands of dollars)
 
(Thousands of dollars)
Sales to unaffiliated customers $1,375,738
 $7,168,983
 $373,738
 $8,918,459
Intersegment revenues 675,839
 506,671
 5,623
 1,188,133
Total revenues 2,051,577
 7,675,654
 379,361
 10,106,592
Cost of sales and fuel (exclusive of depreciation and items shown separately below) (1,331,542) (6,321,377) (30,561) (7,683,480)
NGL and condensate sales $1,224,378
 $7,910,833
 $
 $9,135,211
Residue natural gas sales 966,149
 
 1,244
 967,393
Gathering, processing and exchange services revenue 164,299
 414,238
 
 578,537
Transportation and storage revenue 
 197,483
 466,266
 663,749
Other 13,813
 9,962
 4,477
 28,252
Total revenues (c) 2,368,639
 8,532,516
 471,987
 11,373,142
Cost of sales and fuel (exclusive of depreciation and operating costs) (1,302,310) (6,690,918) (4,628) (7,997,856)
Operating costs (285,599) (327,597) (115,628) (728,824) (368,352) (456,892) (157,230) (982,474)
Equity in net earnings from investments 10,742
 54,513
 74,435
 139,690
 (6,292) 65,123
 95,710
 154,541
Other 1,600
 (1,574) 5,530
 5,556
Noncash compensation expense and other 10,965
 15,936
 2,977
 29,878
Segment adjusted EBITDA $446,778
 $1,079,619
 $313,137
 $1,839,534
 $702,650
 $1,465,765
 $408,816
 $2,577,231
                
Depreciation and amortization $(178,548) $(163,303) $(46,718) $(388,569) $(219,519) $(196,132) $(57,250) $(472,901)
Investments in unconsolidated affiliates $34,426
 $439,393
 $388,025
 $861,844
Total assets $5,320,666
 $8,347,961
 $1,946,318
 $15,614,945
 $6,795,744
 $12,551,476
 $2,094,072
 $21,441,292
Capital expenditures $410,485
 $105,861
 $96,274
 $612,620
 $926,489
 $2,796,604
 $99,221
 $3,822,314
(a) - TheOur Natural Gas Liquids segment has regulated and nonregulated operations. TheOur Natural Gas Liquids segment’s regulated operations had revenues of $1.4 billion, of which $1.2 billion related to sales within the segment, and cost of sales and fuel of $496.8 million.
(b) - Our Natural Gas Pipelines segment has regulated and nonregulated operations. Our Natural Gas Pipelines segment’s regulated operations had revenues of $285.3 million and cost of sales and fuel of $20.0 million.
(c) - Intersegment revenues for the Natural Gas Gathering and Processing segment totaled $1.2 billion. Intersegment revenues for the Natural Gas Liquids and Natural Gas Pipelines segments were not material.


Year Ended December 31, 2019 
Total
Segments
 
Other and
Eliminations
 Total
  
(Thousands of dollars)
Reconciliations of total segments to consolidated      
NGL and condensate sales $9,135,211
 $(1,190,424) $7,944,787
Residue natural gas sales 967,393
 (1,418) 965,975
Gathering, processing and exchange services revenue 578,537
 
 578,537
Transportation and storage revenue 663,749
 (15,646) 648,103
Other 28,252
 (1,287) 26,965
Total revenues (a) $11,373,142
 $(1,208,775) $10,164,367
       
Cost of sales and fuel (exclusive of depreciation and operating costs) $(7,997,856) $1,209,816
 $(6,788,040)
Operating costs $(982,474) $(390) $(982,864)
Depreciation and amortization $(472,901) $(3,634) $(476,535)
Equity in net earnings from investments $154,541
 $
 $154,541
Investments in unconsolidated affiliates $861,844
 $
 $861,844
Total assets $21,441,292
 $370,829
 $21,812,121
Capital expenditures $3,822,314
 $26,035
 $3,848,349
(a) - Noncustomer revenue for the year ended December 31, 2019, totaled $139.6 million related primarily to gains from derivatives on commodity contracts.

Year Ended December 31, 2018 
Natural Gas
Gathering and
Processing
 
Natural Gas
Liquids (a)
 
Natural Gas
Pipelines (b)
 
Total
Segments
  
(Thousands of dollars)
NGL and condensate sales $1,775,991
 $10,319,847
 $
 $12,095,838
Residue natural gas sales 1,084,162
 
 9,772
 1,093,934
Gathering, processing and exchange services revenue 163,194
 404,897
 
 568,091
Transportation and storage revenue 
 199,018
 414,969
 613,987
Other 11,230
 10,816
 6,994
 29,040
Total revenues (c) 3,034,577
 10,934,578
 431,735
 14,400,890
Cost of sales and fuel (exclusive of depreciation and operating costs) (2,041,448) (9,176,813) (15,984) (11,234,245)
Operating costs (368,939) (394,115) (144,259) (907,313)
Equity in net earnings from investments 410
 67,126
 90,847
 158,383
Noncash compensation expense and other 7,007
 9,829
 3,912
 20,748
Segment adjusted EBITDA $631,607
 $1,440,605
 $366,251
 $2,438,463
         
Depreciation and amortization $(196,090) $(174,007) $(55,118) $(425,215)
Investments in unconsolidated affiliates $42,630
 $451,040
 $475,480
 $969,150
Total assets $6,078,473
 $9,663,640
 $2,131,669
 $17,873,782
Capital expenditures $694,611
 $1,306,341
 $119,185
 $2,120,137
(a) - Our Natural Gas Liquids segment has regulated and nonregulated operations. Our Natural Gas Liquids segment’s regulated operations had revenues of $1.2 billion, of which $992.8 million$1.1 billion related to sales within the segment, and cost of sales and fuel of $458.7 million and operating income of $467.9$506.0 million.
(b) - TheOur Natural Gas Pipelines segment has regulated and nonregulated operations. TheOur Natural Gas Pipelines segment’s regulated operations had revenues of $238.7$266.6 million and cost of sales and fuel of $30.0 million$26.0 million.
(c) - Intersegment revenues for the Natural Gas Gathering and operating income of $100.8 million.Processing segment totaled $1.8 billion. Intersegment revenues for the Natural Gas Liquids and Natural Gas Pipelines segments were not material.

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Year Ended December 31, 2016 
Total
Segments
 
Other and
Eliminations
 Total
Year Ended December 31, 2018 
Total
Segments
 
Other and
Eliminations
 Total
 
(Thousands of dollars)
 
(Thousands of dollars)
Reconciliations of total segments to consolidated            
Sales to unaffiliated customers $8,918,459
 $2,475
 $8,920,934
Intersegment revenues 1,188,133
 (1,188,133) 
Total revenues $10,106,592
 $(1,185,658) $8,920,934
NGL and condensate sales $12,095,838
 $(1,794,342) $10,301,496
Residue natural gas sales 1,093,934
 (2,832) 1,091,102
Gathering, processing and exchange services revenue 568,091
 (21) 568,070
Transportation and storage revenue 613,987
 (10,550) 603,437
Other 29,040
 51
 29,091
Total revenues (a) $14,400,890
 $(1,807,694) $12,593,196
            
Cost of sales and fuel (exclusive of depreciation and operating costs) $(7,683,480) $1,187,356
 $(6,496,124) $(11,234,245) $1,811,537
 $(9,422,708)
Operating costs $(728,824) $(28,360) $(757,184) $(907,313) $245
 $(907,068)
Depreciation and amortization $(388,569) $(3,016) $(391,585) $(425,215) $(3,342) $(428,557)
Equity in net earnings from investments $139,690
 $
 $139,690
 $158,383
 $
 $158,383
Investments in unconsolidated affiliates $969,150
 $
 $969,150
Total assets $15,614,945
 $523,806
 $16,138,751
 $17,873,782
 $357,889
 $18,231,671
Capital expenditures $612,620
 $12,014
 $624,634
 $2,120,137
 $21,338
 $2,141,475

(a) - Noncustomer revenue for the year ended December 31, 2018, totaled $(16.2) million related primarily to losses from derivatives on commodity contracts.

Year Ended December 31, 2015 
Natural Gas
Gathering and
Processing
 
Natural Gas
Liquids (a)
 
Natural Gas
Pipelines (b)
 
Total
Segments
Year Ended December 31, 2017 
Natural Gas
Gathering and
Processing
 
Natural Gas
Liquids (a)
 
Natural Gas
Pipelines (b)
 
Total
Segments
 
(Thousands of dollars)
 
(Thousands of dollars)
Sales to unaffiliated customers $1,187,390
 $6,248,002
 $325,676
 $7,761,068
 $1,750,655
 $10,009,576
 $411,490
 $12,171,721
Intersegment revenues 649,726
 331,697
 6,771
 988,194
 1,275,919
 616,628
 8,442
 1,900,989
Total revenues 1,837,116
 6,579,699
 332,447
 8,749,262
 3,026,574
 10,626,204

419,932

14,072,710
Cost of sales and fuel (exclusive of depreciation and items shown separately below) (1,265,617) (5,328,256) (34,481) (6,628,354)
Cost of sales and fuel (exclusive of depreciation and operating costs) (2,216,355) (9,176,494) (43,424) (11,436,273)
Operating costs (272,418) (314,505) (105,720) (692,643) (307,376) (358,278) (125,308) (790,962)
Equity in net earnings from investments 17,863
 38,696
 68,741
 125,300
 12,098
 59,876
 87,304
 159,278
Other 1,610
 (3,342) 13,993
 12,261
 3,531
 3,631
 1,314
 8,476
Segment adjusted EBITDA $318,554
 $972,292
 $274,980
 $1,565,826
 $518,472
 $1,154,939
 $339,818
 $2,013,229
                
Depreciation and amortization $(150,008) $(158,709) $(43,479) $(352,196) $(184,923) $(167,277) $(51,025) $(403,225)
Impairment of long-lived assets $(73,681) $(9,992) $
 $(83,673)
Impairment of equity investments $(180,583) $
 $
 $(180,583)
Impairment of long-lived assets and equity investments $(20,240) $
 $
 $(20,240)
Investments in unconsolidated affiliates $55,841
 $457,467
 $489,848
 $1,003,156
Total assets $5,123,450
 $8,017,799
 $1,851,857
 $14,993,106
 $5,495,163
 $8,782,700
 $2,055,020
 $16,332,883
Capital expenditures $887,938
 $226,135
 $58,215
 $1,172,288
 $284,205
 $114,267
 $95,564
 $494,036
(a) - TheOur Natural Gas Liquids segment has regulated and nonregulated operations. TheOur Natural Gas Liquids segment’s regulated operations had revenues of $954.8 million,$1.2 billion, of which $770.1 million$1.0 billion related to sales within the segment, and cost of sales and fuel of $412.6 million and operating income of $306.9$497.4 million.
(b) - TheOur Natural Gas Pipelines segment has regulated and nonregulated operations. TheOur Natural Gas Pipelines segment’s regulated operations had revenues of $266.9$264.9 million and cost of sales and fuel of $31.1 million and operating income of $103.7$44.0 million.

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Year Ended December 31, 2015 
Total
Segments
 
Other and
Eliminations
 Total
Year Ended December 31, 2017 
Total
Segments
 
Other and
Eliminations
 Total
 
(Thousands of dollars)
 
(Thousands of dollars)
Reconciliations of total segments to consolidated            
Sales to unaffiliated customers $7,761,068
 $2,138
 $7,763,206
 $12,171,721
 $2,186
 $12,173,907
Intersegment revenues 988,194
 (988,194) 
 1,900,989
 (1,900,989) 
Total revenues $8,749,262
 $(986,056) $7,763,206
 $14,072,710
 $(1,898,803) $12,173,907
            
Cost of sales and fuel (exclusive of depreciation and operating costs) $(6,628,354) $987,302
 $(5,641,052) $(11,436,273) $1,898,228
 $(9,538,045)
Operating costs $(692,643) $(688) $(693,331) $(790,962) $(31,748) $(822,710)
Depreciation and amortization $(352,196) $(2,424) $(354,620) $(403,225) $(3,110) $(406,335)
Impairment of long-lived assets $(83,673) $
 $(83,673)
Impairment of equity investments $(180,583) $
 $(180,583)
Impairment of long-lived assets and equity investments $(20,240) $
 $(20,240)
Equity in net earnings from investments $125,300
 $
 $125,300
 $159,278
 $
 $159,278
Investments in unconsolidated affiliates $1,003,156
 $
 $1,003,156
Total assets $14,993,106
 $453,005
 $15,446,111
 $16,332,883
 $513,054
 $16,845,937
Capital expenditures $1,172,288
 $16,024
 $1,188,312
 $494,036
 $18,357
 $512,393


Year Ended December 31, 2014 
Natural Gas
Gathering and
Processing
 
Natural Gas
Liquids (a)
 
Natural Gas
Pipelines (b)
 
Total
Segments
  
(Thousands of dollars)
Sales to unaffiliated customers $1,478,729
 $10,329,609
 $329,801
 $12,138,139
Sales to affiliated customers 41,214
 
 12,312
 53,526
Intersegment revenues 1,447,665
 215,772
 8,343
 1,671,780
Total revenues 2,967,608
 10,545,381
 350,456
 13,863,445
Cost of sales and fuel (exclusive of depreciation and items shown separately below) (2,305,723) (9,435,296) (21,935) (11,762,954)
Operating costs (257,658) (296,402) (111,037) (665,097)
Equity in net earnings from investments 20,271
 27,326
 69,818
 117,415
Other 672
 (87) 6,900
 7,485
Segment adjusted EBITDA $425,170
 $840,922
 $294,202
 $1,560,294
         
Depreciation and amortization $(123,847) $(124,071) $(43,318) $(291,236)
Impairment of equity investments $(76,412) $
 $
 $(76,412)
Total assets $4,911,283
 $8,143,575
 $1,835,884
 $14,890,742
Capital expenditures $898,896
 $798,048
 $42,991
 $1,739,935
  Years Ended December 31,
  2019 2018 2017
Reconciliation of net income to total segment adjusted EBITDA 
(Thousands of dollars)
Net income $1,278,577
 $1,155,032
 $593,519
Add:      
Interest expense, net of capitalized interest 491,773
 469,620
 485,658
Depreciation and amortization 476,535
 428,557
 406,335
Income taxes 372,414
 362,903
 447,282
Impairment charges 
 
 20,240
Noncash compensation expense 26,699
 37,954
 13,421
Other corporate costs and noncash items (a) (68,767) (15,603) 46,774
Total segment adjusted EBITDA $2,577,231
 $2,438,463
 $2,013,229
(a) - The Natural Gas Liquids segment has regulated and nonregulated operations. The Natural Gas Liquids segment’s regulated operations had revenues of $695.9 million, of which $598.1 millionyear ended December 31, 2019, includes higher equity AFUDC related to sales withinour capital-growth projects compared with 2018 and 2017. The year ended December 31, 2017, includes our April 2017 $20.0 million contribution of Series E Preferred Stock to the segment, costFoundation and costs related to the Merger Transaction of sales and fuel of $309.4 million and operating income of $196.1$30.0 million.
(b) - The Natural Gas Pipelines segment has regulated and nonregulated operations. The Natural Gas Pipelines segment’s regulated operations had revenues of $290.0 million, cost of sales and fuel of $47.7 million and operating income of $106.5 million.

Table of contents

Year Ended December 31, 2014 
Total
Segments
 
Other and
Eliminations
 Total
  
(Thousands of dollars)
Reconciliations of total segments to consolidated      
Sales to unaffiliated customers $12,138,139
 $3,426
 $12,141,565
Sales to affiliated customers 53,526
 
 53,526
Intersegment revenues 1,671,780
 (1,671,780) 
Total revenues $13,863,445
 $(1,668,354) $12,195,091
       
Cost of sales and fuel (exclusive of depreciation and operating costs) $(11,762,954) $1,674,406
 $(10,088,548)
Operating costs $(665,097) $(9,790) $(674,887)
Depreciation and amortization $(291,236) $(3,448) $(294,684)
Impairment of equity investments $(76,412) $
 $(76,412)
Equity in net earnings from investments $117,415
 $
 $117,415
Total assets $14,890,742
 $371,031
 $15,261,773
Capital expenditures $1,739,935
 $39,215
 $1,779,150

  Years Ended December 31,
(Unaudited)
 2016 2015 2014
Reconciliation of net income to total segment adjusted EBITDA 
(Thousands of dollars)
Net income from continuing operations $745,550
 $385,276
 $668,715
Add:      
Interest expense, net of capitalized interest 469,651
 416,787
 356,163
Depreciation and amortization 391,585
 354,620
 294,684
Income taxes 212,406
 136,600
 151,158
Impairment charges 
 264,256
 76,412
Allowance for equity funds used during construction and other 20,342
 8,287
 13,162
Total segment adjusted EBITDA $1,839,534
 $1,565,826
 $1,560,294


T.R.QUARTERLY FINANCIAL DATA (UNAUDITED)


 
First
Quarter
 
Second
Quarter
 
Third
Quarter
 
Fourth
Quarter
Year Ended December 31, 2016 
Year Ended December 31, 2019 
First
Quarter
 
Second
Quarter
 
Third
Quarter
 
Fourth
Quarter
 
(Thousands of dollars except per share amounts)
 
(Thousands of dollars, except per share amounts)
Total revenues $1,774,459
 $2,134,107
 $2,357,907
 $2,654,461
 $2,779,958
 $2,457,575
 $2,263,228
 $2,663,606
Income from continuing operations $175,911
 $180,086
 $194,792
 $194,761
Income (loss) from discontinued operations, net of tax $(952) $(227) $(576) $(296)
Operating income $468,742
 $476,146
 $482,151
 $487,314
Net income $174,959
 $179,859
 $194,216
 $194,465
 $337,208
 $311,963
 $309,155
 $320,251
Net income attributable to ONEOK $83,446
 $85,944
 $92,144
 $90,505
Net income available to common shareholders $336,933
 $311,688
 $308,880
 $319,976
Earnings per share total                
Basic $0.40
 $0.41
 $0.44
 $0.43
 $0.82
 $0.75
 $0.75
 $0.77
Diluted $0.40
 $0.40
 $0.43
 $0.43
 $0.81
 $0.75
 $0.74
 $0.77


Table of contents
Year Ended December 31, 2018 
First
Quarter
 
Second
Quarter
 
Third
Quarter
 
Fourth
Quarter
    
  
(Thousands of dollars except per share amounts)
Total revenues $3,102,077
 $2,960,529
 $3,393,890
 $3,136,700
Operating income $419,699
 $448,366
 $495,534
 $471,865
Net income $266,049
 $282,179
 $313,916
 $292,888
Net income available to common shareholders $264,233
 $280,773
 $312,984
 $292,613
Earnings per share total        
Basic $0.65
 $0.68
 $0.76
 $0.71
Diluted $0.64
 $0.68
 $0.75
 $0.70


  
First
Quarter
 
Second
Quarter
 
Third
Quarter
 
Fourth
Quarter
Year Ended December 31, 2015    
  
(Thousands of dollars except per share amounts)
Total revenues $1,805,306
 $2,128,052
 $1,898,946
 $1,930,902
Income from continuing operations $95,837
 $151,020
 $164,698
 $(26,279)
Income (loss) from discontinued operations, net of tax $(144) $(140) $(3,860) $(1,937)
Net income $95,693
 $150,880
 $160,838
 $(28,216)
Net income attributable to ONEOK $60,800
 $76,505
 $82,157
 $25,515
Earnings per share total        
Basic $0.29
 $0.36
 $0.39
 $0.13
Diluted $0.29
 $0.36
 $0.39
 $0.12

The fourth quarter 2015 includes noncash impairment charges of $264.3 million related to long-lived assets and equity investments.


ITEM 9.S.CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING ANDSUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL DISCLOSUREINFORMATION

ONEOK and ONEOK Partners are issuers of certain public debt securities. We, ONEOK Partners and the Intermediate Partnership have cross guarantees in place for the indebtedness of ONEOK and ONEOK Partners. The Intermediate Partnership holds all of ONEOK Partners’ interests and equity in its subsidiaries, as well as a 50% interest in Northern Border Pipeline. In lieu of providing separate financial statements for each subsidiary issuer and guarantor, we have included the accompanying condensed consolidating financial statements based on Rule 3-10 of the SEC’s Regulation S-X. We have presented each of the parent and subsidiary issuers in separate columns in this single set of condensed consolidating financial statements.

For purposes of the following footnote:
we are referred to as “Parent Issuer and Guarantor”;
ONEOK Partners is referred to as “Subsidiary Issuer and Guarantor”;
the Intermediate Partnership is referred to as “Guarantor Subsidiary”; and
the “Non-Guarantor Subsidiaries” are all subsidiaries other than the Guarantor Subsidiary and Subsidiary Issuer and Guarantor.

The following supplemental condensed consolidating financial information is presented on an equity-method basis reflecting the separate accounts of ONEOK, ONEOK Partners and the Intermediate Partnership, the combined accounts of the Non-Guarantor Subsidiaries, the combined consolidating adjustments and eliminations, and our consolidated amounts for the periods indicated.


Condensed Consolidating Statements of Income
 Year Ended December 31, 2019
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
 
(Millions of dollars)
Revenues           
Commodity sales$
 $
 $
 $8,916.1
 $
 $8,916.1
Services
 
 
 1,250.4
 (2.1) 1,248.3
Total revenues
 
 
 10,166.5
 (2.1) 10,164.4
Cost of sales and fuel (exclusive of items shown separately below)
 
 
 6,788.0
 
 6,788.0
Operating expenses
 
 
 1,461.5
 (2.1) 1,459.4
(Gain) loss on sale of assets
 
 2.7
 (0.1) 
 2.6
Operating income
 
 (2.7) 1,917.1
 
 1,914.4
Equity in net earnings from investments1,898.7
 1,906.2
 1,908.9
 116.3
 (5,675.6) 154.5
Other income (expense), net34.4
 305.7
 308.3
 42.1
 (616.6) 73.9
Interest expense, net(287.4) (308.3) (308.3) (204.4) 616.6
 (491.8)
Income before income taxes1,645.7
 1,903.6
 1,906.2
 1,871.1
 (5,675.6) 1,651.0
Income taxes(367.1) 
 
 (5.3) 
 (372.4)
Net income1,278.6
 1,903.6
 1,906.2
 1,865.8
 (5,675.6) 1,278.6
Less: Preferred stock dividends1.1
 
 
 
 
 1.1
Net income available to common shareholders$1,277.5
 $1,903.6
 $1,906.2
 $1,865.8
 $(5,675.6) $1,277.5
            
Net income$1,278.6
 $1,903.6
 $1,906.2
 $1,865.8
 $(5,675.6) $1,278.6
Other comprehensive income (loss), net of tax(183.8) (2.6) (20.9) (20.5) 42.0
 (185.8)
Comprehensive income$1,094.8
 $1,901.0
 $1,885.3
 $1,845.3
 $(5,633.6) $1,092.8


 Year Ended December 31, 2018
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
 
(Millions of dollars)
Revenues           
Commodity sales$
 $
 $
 $11,395.6
 $
 $11,395.6
Services
 
 
 1,199.7
 (2.1) 1,197.6
Total revenues
 
 
 12,595.3
 (2.1) 12,593.2
Cost of sales and fuel (exclusive of items shown separately below)
 
 
 9,422.7
 
 9,422.7
Operating expenses(0.6) 
 
 1,338.3
 (2.1) 1,335.6
Gain on sale of assets
 
 
 (0.6) 
 (0.6)
Operating income0.6
 
 
 1,834.9
 
 1,835.5
Equity in net earnings from investments1,655.6
 1,660.5
 1,660.5
 116.3
 (4,934.5) 158.4
Other income (expense), net29.6
 315.1
 315.1
 (36.0) (630.2) (6.4)
Interest expense, net(179.4) (315.1) (315.1) (290.2) 630.2
 (469.6)
Income before income taxes1,506.4
 1,660.5
 1,660.5

1,625.0
 (4,934.5) 1,517.9
Income taxes(354.7) 
 
 (8.2) 
 (362.9)
Net income1,151.7
 1,660.5
 1,660.5
 1,616.8
 (4,934.5) 1,155.0
Less: Net income attributable to noncontrolling interests
 
 
 3.3
 
 3.3
Net income attributable to ONEOK1,151.7
 1,660.5
 1,660.5
 1,613.5
 (4,934.5) 1,151.7
Less: Preferred stock dividends1.1
 
 
 
 
 1.1
Net income available to common shareholders$1,150.6
 $1,660.5
 $1,660.5
 $1,613.5
 $(4,934.5) $1,150.6
            
Net income$1,151.7
 $1,660.5
 $1,660.5
 $1,616.8
 $(4,934.5) $1,155.0
Other comprehensive income (loss), net of tax(39.5) 101.1
 85.9
 62.6
 (171.7) 38.4
Comprehensive income1,112.2
 1,761.6
 1,746.4
 1,679.4
 (5,106.2) 1,193.4
Less: Comprehensive income attributable to noncontrolling interests
 
 
 3.3
 
 3.3
Comprehensive income attributable to ONEOK$1,112.2
 $1,761.6
 $1,746.4
 $1,676.1
 $(5,106.2) $1,190.1

 Year Ended December 31, 2017
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
 
(Millions of dollars)
Revenues           
Commodity sales$
 $
 $
 $9,862.7
 $
 $9,862.7
Services
 
 
 2,313.2
 (2.0) 2,311.2
Total revenues
 
 
 12,175.9
 (2.0) 12,173.9
Cost of sales and fuel (exclusive of items shown separately below)
 
 
 9,538.0
 
 9,538.0
Operating expenses17.8
 
 9.2
 1,204.0
 (2.0) 1,229.0
Impairment of long-lived assets
 
 
 16.0
 
 16.0
Gain on sale of assets
 
 
 (0.9) 
 (0.9)
Operating income(17.8) 
 (9.2) 1,418.8
 
 1,391.8
Equity in net earnings from investments1,236.6
 1,215.7
 1,224.9
 100.7
 (3,618.6) 159.3
Impairment of equity investments
 
 
 (4.3) 
 (4.3)
Other income (expense), net(12.3) 353.1
 353.1
 (8.0) (706.2) (20.3)
Interest expense, net(137.1) (353.1) (353.1) (348.6) 706.2
 (485.7)
Income before income taxes1,069.4
 1,215.7
 1,215.7
 1,158.6
 (3,618.6) 1,040.8
Income taxes(480.2) 
 
 32.9
 
 (447.3)
Net income589.2
 1,215.7
 1,215.7
 1,191.5
 (3,618.6) 593.5
Less: Net income attributable to noncontrolling interests201.4
 
 
 4.3
 
 205.7
Net income attributable to ONEOK387.8
 1,215.7
 1,215.7
 1,187.2
 (3,618.6) 387.8
Less: Preferred stock dividends0.8
 
 
 
 
 0.8
Net income available to common shareholders$387.0
 $1,215.7
 $1,215.7
 $1,187.2
 $(3,618.6) $387.0
            
Net income$589.2
 $1,215.7
 $1,215.7
 $1,191.5
 $(3,618.6) $593.5
Other comprehensive income (loss), net of tax17.4
 13.2
 27.9
 34.5
 (55.9) 37.1
Comprehensive income606.6
 1,228.9
 1,243.6
 1,226.0
 (3,674.5) 630.6
Less: Comprehensive income attributable to noncontrolling interests232.4
 
 
 4.3
 
 236.7
Comprehensive income attributable to ONEOK$374.2
 $1,228.9
 $1,243.6
 $1,221.7
 $(3,674.5) $393.9


Condensed Consolidating Balance Sheets
 December 31, 2019
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
Assets
(Millions of dollars)
Current assets           
Cash and cash equivalents$21.0
 $
 $
 $
 $
 $21.0
Accounts receivable, net
 
 
 835.1
 
 835.1
Materials and supplies
 
 
 201.7
 
 201.7
Natural gas and NGLs in storage
 
 
 304.9
 
 304.9
Other current assets12.4
 
 
 95.2
 
 107.6
Total current assets33.4
 
 
 1,436.9
 
 1,470.3
Property, plant and equipment           
Property, plant and equipment166.6
 
 
 21,884.9
 
 22,051.5
Accumulated depreciation and amortization99.5
 
 
 3,603.3
 
 3,702.8
Net property, plant and equipment67.1
 
 
 18,281.6
 
 18,348.7
Investments and other assets           
Investments6,732.6
 4,101.4
 11,466.3
 769.9
 (22,208.4) 861.8
Intercompany notes receivable8,950.9
 6,903.2
 
 
 (15,854.1) 
Other assets139.9
 
 
 992.1
 (0.7) 1,131.3
Total investments and other assets15,823.4
 11,004.6
 11,466.3
 1,762.0
 (38,063.2) 1,993.1
Total assets$15,923.9
 $11,004.6
 $11,466.3
 $21,480.5
 $(38,063.2) $21,812.1
Liabilities and equity           
Current liabilities           
Current maturities of long-term debt$
 $
 $
 $7.7
 $
 $7.7
Short-term borrowings220.0
 
 
 
 
 220.0
Accounts payable23.8
 
 
 1,186.1
 
 1,209.9
Other current liabilities243.8
 63.3
 
 275.6
 
 582.7
Total current liabilities487.6
 63.3
 
 1,469.4
 
 2,020.3
            
Intercompany payables
 
 7,364.9
 8,489.2
 (15,854.1) 
            
Long-term debt, excluding current maturities8,421.1
 4,045.1
 
 13.5
 
 12,479.7
            
Deferred credits and other liabilities           
Deferred income taxes417.1
 
 
 119.7
 (0.7) 536.1
Other deferred credits372.1
 
 
 177.9
 
 550.0
Total deferred credits and other liabilities789.2
 
 
 297.6
 (0.7) 1,086.1
            
Commitments and contingencies


 


 


 


 


 


            
Equity6,226.0
 6,896.2
 4,101.4
 11,210.8
 (22,208.4) 6,226.0
Total liabilities and equity$15,923.9
 $11,004.6
 $11,466.3
 $21,480.5
 $(38,063.2) $21,812.1


 December 31, 2018
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
Assets
(Millions of dollars)
Current assets           
Cash and cash equivalents$12.0
 $
 $
 $
 $
 $12.0
Accounts receivable, net
 
 
 819.0
 
 819.0
Materials and supplies
 
 
 141.2
 
 141.2
Natural gas and NGLs in storage
 
 
 296.7
 
 296.7
Other current assets29.1
 
 
 100.6
 
 129.7
Total current assets41.1
 
 
 1,357.5
 
 1,398.6
Property, plant and equipment           
Property, plant and equipment145.5
 
 
 17,885.5
 
 18,031.0
Accumulated depreciation and amortization92.0
 
 
 3,172.3
 
 3,264.3
Net property, plant and equipment53.5
 
 
 14,713.2
 
 14,766.7
Investments and other assets           
Investments6,153.5
 3,548.1
 9,721.6
 791.1
 (19,245.1) 969.2
Intercompany notes receivable5,308.6
 7,701.5
 1,528.0
 
 (14,538.1) 
Other assets115.9
 
 
 982.3
 (1.0) 1,097.2
Total investments and other assets11,578.0
 11,249.6
 11,249.6
 1,773.4
 (33,784.2) 2,066.4
Total assets$11,672.6
 $11,249.6
 $11,249.6
 $17,844.1
 $(33,784.2) $18,231.7
Liabilities and equity           
Current liabilities           
Current maturities of long-term debt$
 $500.0
 $
 $7.7
 $
 $507.7
Accounts payable31.3
 
 
 1,085.0
 
 1,116.3
Other current liabilities123.2
 81.0
 
 280.2
 
 484.4
Total current liabilities154.5
 581.0
 
 1,372.9
 
 2,108.4
            
Intercompany payables
 
 7,701.5
 6,836.6
 (14,538.1) 
            
Long-term debt, excluding current maturities4,510.7
 4,341.4
 
 21.2
 
 8,873.3
            
Deferred credits and other liabilities

 

 

 

 

 

Deferred income taxes112.3
 
 
 108.4
 (1.0) 219.7
Other deferred credits315.6
 
 
 135.2
 
 450.8
Total deferred credits and other liabilities427.9
 
 
 243.6
 (1.0) 670.5
            
Commitments and contingencies


 


 


 


 


 


            
Equity6,579.5
 6,327.2
 3,548.1
 9,369.8
 (19,245.1) 6,579.5
Total liabilities and equity$11,672.6
 $11,249.6
 $11,249.6
 $17,844.1
 $(33,784.2) $18,231.7


Condensed Consolidating Statements of Cash Flows
 Year Ended December 31, 2019
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
 
(Millions of dollars)
Operating activities           
Cash provided by operating activities$1,010.1
 $1,332.9
 $68.9
 $2,198.9
 $(2,664.0) $1,946.8
Investing activities           
Capital expenditures(25.6) 
 
 (3,822.7) 
 (3,848.3)
Other investing activities
 
 74.6
 4.9
 
 79.5
Cash provided by (used in) investing activities(25.6) 
 74.6
 (3,817.8) 
 (3,768.8)
Financing activities           
Dividends paid(1,457.6) (1,332.0) (1,332.0) 
 2,664.0
 (1,457.6)
Intercompany borrowings (advances), net(3,618.6) 801.8
 1,188.5
 1,628.3
 
 
Short-term borrowings, net220.0
 
 
 
 
 220.0
Issuance of long-term debt, net of discounts4,185.4
 
 
 
 
 4,185.4
Repayment of long-term debt(249.6) (800.0) 
 (7.7) 
 (1,057.3)
Issuance of common stock29.0
 
 
 
 
 29.0
Other, net(84.1) (2.7) 
 (1.7) 
 (88.5)
Cash provided by (used in) financing activities(975.5) (1,332.9) (143.5) 1,618.9
 2,664.0
 1,831.0
Change in cash and cash equivalents9.0
 
 
 
 
 9.0
Cash and cash equivalents at beginning of period12.0
 
 
 
 
 12.0
Cash and cash equivalents at end of period$21.0
 $
 $
 $
 $
 $21.0

 Year Ended December 31, 2018
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
 
(Millions of dollars)
Operating activities           
Cash provided by operating activities$1,325.1
 $1,344.7
 $67.9
 $2,113.0
 $(2,664.0) $2,186.7
Investing activities           
Capital expenditures(18.8) 
 
 (2,122.7) 
 (2,141.5)
Other investing activities
 
 15.3
 11.3
 
 26.6
Cash provided by (used in) investing activities(18.8) 
 15.3
 (2,111.4) 
 (2,114.9)
Financing activities           
Dividends paid(1,335.1) (1,332.0) (1,332.0) 
 2,664.0
 (1,335.1)
Distributions to noncontrolling interests
 
 
 (3.5) 
 (3.5)
Intercompany borrowings (advances), net(2,154.4) 912.3
 1,248.8
 (6.7) 
 
Repayment of short-term borrowings, net(614.7) 
 
 
 
 (614.7)
Issuance of long-term debt, net of discounts1,795.8
 
 
 
 
 1,795.8
Repayment of long-term debt
 (925.0) 
 (7.7) 
 (932.7)
Issuance of common stock1,204.0
 
 
 
 
 1,204.0
Acquisition of noncontrolling interests(195.0) 
 
 
 
 (195.0)
Other, net(32.1) 
 
 16.3
 
 (15.8)
Cash used in financing activities(1,331.5) (1,344.7) (83.2) (1.6) 2,664.0
 (97.0)
Change in cash and cash equivalents(25.2) 
 
 
 
 (25.2)
Cash and cash equivalents at beginning of period37.2
 
 
 
 
 37.2
Cash and cash equivalents at end of period$12.0
 $
 $
 $
 $
 $12.0


 Year Ended December 31, 2017
 
Parent
Issuer &
Guarantor
 
Subsidiary
Issuer &
Guarantor
 
Guarantor
Subsidiary
 
Combined
Non-Guarantor
Subsidiaries
 
Consolidating
Entries and
Other
 Total
 
(Millions of dollars)
Operating activities           
Cash provided by operating activities$947.4
 $1,348.3
 $59.0
 $1,353.7
 $(2,393.0) $1,315.4
Investing activities           
Capital expenditures
 
 
 (512.4) 
 (512.4)
Contributions to unconsolidated affiliates
 
 (83.0) (4.9) 
 (87.9)
Other investing activities
 
 14.8
 17.9
 
 32.7
Cash used in investing activities
 
 (68.2) (499.4) 
 (567.6)
Financing activities           
Dividends paid(829.4) (1,332.0) (1,332.0) 
 2,664.0
 (829.4)
Distributions to noncontrolling interests
 
 
 (5.3) (271.0) (276.3)
Intercompany borrowings (advances), net(2,500.7) 2,001.2
 1,340.8
 (841.3) 
 
Borrowing (repayment) of short-term borrowings, net614.7
 (1,110.3) 
 
 
 (495.6)
Issuance of long-term debt, net of discounts1,190.5
 
 
 
 
 1,190.5
Repayment of long-term debt(87.1) (900.0) 
 (7.7) 
 (994.8)
Issuance of common stock471.4
 
 
 
 
 471.4
Other, net(18.1) (7.2) 
 
 
 (25.3)
Cash provided by (used in) financing activities(1,158.7) (1,348.3) 8.8
 (854.3) 2,393.0
 (959.5)
Change in cash and cash equivalents(211.3) 
 (0.4) 
 
 (211.7)
Cash and cash equivalents at beginning of period248.5
 
 0.4
 
 
 248.9
Cash and cash equivalents at end of period$37.2
 $
 $
 $
 $
 $37.2



ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
FINANCIAL DISCLOSURE

None.


ITEM 9A.    CONTROLS AND PROCEDURES


Evaluation of Disclosure Controls and Procedures


Our Chief Executive Officer (Principal Executive Officer) and Chief Financial Officer (Principal Financial Officer) have concluded that our disclosure controls and procedures were effective as of the end of the period covered by this report based on the evaluation of the controls and procedures required by Rule 13a-15(b)Rules 13a-15(e) and 15d-15(e) of the Exchange Act.


Management’s Report on Internal Control Over Financial Reporting


Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act Rule 13a-15(f). Under the supervision and with the participation of our management, including our Principal Executive Officer and Principal Financial Officer, we evaluated the effectiveness of our internal control over financial reporting based on the framework in Internal Control-Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. Because of inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Based on our evaluation under that framework, and applicable SEC rules, our management concluded that our internal control over financial reporting was effective as of December 31, 20162019.


The effectiveness of our internal control over financial reporting as of December 31, 20162019, has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report which is included herein (Item 8).


Changes in Internal Control Over Financial Reporting


There have been no changes in our internal control over financial reporting during the quarter ended December 31, 20162019, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.


ITEM 9B.    OTHER INFORMATION


Not applicable.



PART III


ITEM 10.    DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE


Directors of the Registrant


Information concerning our directors is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Executive Officers of the Registrant


Information concerning our executive officers is included in Part I, Item 1, Business, of this Annual Report.


Compliance with Section 16(a) of the Exchange Act


Information on compliance with Section 16(a) of the Exchange Act is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Code of Ethics


Information concerning the code of ethics, or code of business conduct, is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Nominating Committee Procedures


Information concerning the Nominating Committee procedures is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Audit Committee


Information concerning the Audit Committee is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Audit Committee Financial Experts


Information concerning the Audit Committee Financial Experts is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


ITEM 11.    EXECUTIVE COMPENSATION


Information on executive compensation is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


ITEM 12.SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS


Security Ownership of Certain Beneficial Owners


Information concerning the ownership of certain beneficial owners is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Security Ownership of Management


Information on security ownership of directors and officers is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.



Equity Compensation Plan Information


The following table sets forth certain information concerning our equity compensation plans as of December 31, 2016:2019:
 
Number of Securities
to be Issued
Upon Exercise of
Outstanding Options,
Warrants and Rights
 
Weighted-Average
Exercise Price of
Outstanding Options,
Warrants and Rights
 
Number of Securities
Remaining Available For
Future Issuance Under
Equity Compensation
Plans (Excluding
Securities in Column (a))
 
Number of Securities
to be Issued
Upon Exercise of
Outstanding Options,
Warrants and Rights
 
Weighted-Average
Exercise Price of
Outstanding Options,
Warrants and Rights
 
Number of Securities
Remaining Available For
Future Issuance Under
Equity Compensation
Plans (Excluding
Securities in Column (a))
Plan Category (a) (b) (c) (a) (b) (3) (c)
Equity compensation plans
approved by security holders (1)
 2,585,484
 $41.25
 4,565,666
  2,076,295
 $64.33
 8,960,329
 
Equity compensation plans
not approved by security holders (2)
 274,999
 $57.41
(3) 1,007,204
  350,029
 $75.67
 
 
Total 2,860,483
 $42.81
 5,572,870
  2,426,324
 $65.96
 8,960,329
 
(1) - Includes shares granted under our Employee Stock Purchase Plan and Employee Stock Award Program and restricted stock incentive unitsunit awards and performance-unitperformance unit awards granted under our former Long-Term Incentive Plan, andour former Equity Compensation Plan and our Equity Incentive Plan. For a brief description of the material features of these plans, see Note KJ of the Notes to Consolidated Financial Statements in this Annual Report. Column (a) includes shares based on 100% of the performance units vesting at the end of the three-year performance period. Column (c) includes 1,779,830, 149,650, 249,8711,211,710, 133,075 and 2,386,3157,615,544 shares available for future issuance under our Employee Stock Purchase Plan, Employee Stock Award Program Long-Term Incentive Plan and Equity CompensationIncentive Plan, respectively.
(2) - Includes our Employee Non-Qualified Deferred CompensationNQDC Plan, Deferred Compensation Plan for Non-Employee Directors and our former Stock Compensation Plan for Non-Employee Directors. For a brief description of the material features of these plans, see Note KJ of the Notes to Consolidated Financial Statements in this Annual Report.
(3) - Compensation deferred into our common stock under our Employee Non-Qualified Deferredformer Equity Compensation Plan and our Deferred Compensation Plan for Non-Employee Directors is distributed to participants at fair market value on the date of distribution. The price used for these plans to calculate the weighted-average exercise price in the table is $57.41,$75.67, which represents the 20162019 year-end closing price of our common stock on the NYSE.


ITEM 13.CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE


Information on certain relationships and related transactions and director independence is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


ITEM 14.
ITEM 14.    PRINCIPAL ACCOUNTING FEES AND SERVICES


Information concerning the principal accountant’s fees and services is set forth in our 20172020 definitive Proxy Statement and is incorporated herein by this reference.


Table of contents

PART IV


ITEM 15.EXHIBITS, FINANCIAL STATEMENT SCHEDULES


(1) Financial StatementsPage No.
    
 (a)Report of Independent Registered Public Accounting Firm7354-55
    
 (b)
Consolidated Statements of Income for the years ended
December 31, 2016, 20152019, 2018 and 20142017
7456
    
 (c)
Consolidated Statements of Comprehensive Income for the years ended
December 31, 2016, 20152019, 2018 and 20142017
7557
    
 (d)Consolidated Balance Sheets as of December 31, 20162019 and 2015201876-7758-59
    
 (e)
Consolidated Statements of Cash Flows for the years ended
December 31, 2016, 20152019, 2018 and 20142017
7961
    
 (f)
Consolidated Statements of Shareholder’sChanges in Equity for the years ended
December 31, 2016, 20152019, 2018 and 20142017
80-8162-63
    
 (g)Notes to Consolidated Financial Statements82-12964-111
    
(2) Financial Statements Schedules 
    
 All schedules have been omitted because of the absence of conditions under which they are required.
(3) Exhibits
   
 2
   
 2.1
   
 3Not used.
   
 3.1Not used.
3.2Not used.
3.3Not used.
3.4
   
 3.5
Amended and Restated Certificate of Incorporation of ONEOK, Inc., dated May 15, 2008, as amended
(incorporated by reference from Exhibit 3.1 to ONEOK, Inc.’s Quarterly Report on Form 10-Q for the
quarter ended June, 30, 2012, filed August 1, 2012 (File No. 1-13643)).
3.6Not used.
Table of contents

4
   
 4.1
   

 4.2Not used
   
 4.3
 
4.4
   
 4.5
   
 4.6
   
 4.7
   
 4.8
   
 4.9
   
 4.10
   
 4.11Not used.
4.12Not used.
4.13Not used.
4.14Second
   
Table of contents

 4.154.12Third
4.16
Tenth Supplemental Indenture, dated September 12, 2013, among ONEOK Partners, L.P., ONEOK Partners
Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 3.200 percent
Senior Notes due 2018 (incorporated by reference to Exhibit 4.2 to ONEOK Partners, L.P.’s Current Report
on Form 8-K filed September 12, 2013 (File No. 1-12202)).
   
 4.174.13
4.18
Twelfth Supplemental Indenture, dated September 12, 2013, among ONEOK Partners, L.P., ONEOK
Partners Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 6.200
percent Senior Notes due 2043 (incorporated by reference to Exhibit 4.4 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed September 12, 2013 (File No. 1-12202)).
4.19
Indenture, dated September 25, 2006, between ONEOK Partners, L.P. and Wells Fargo Bank, N.A., as
trustee (incorporated by reference tofrom Exhibit 4.1 to ONEOK, Partners, L.P.’s Current Report on Form 8-K
filed September 26, 2006July 3, 2017 (File No. 1-12202)).
4.20Eighth Supplemental Indenture, dated  September 13, 2012, among ONEOK Partners, L.P., ONEOK
Partners Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the
2.000 percent Senior Notes due 2017 (incorporated by reference from Exhibit 4.2 to ONEOK Partners, L.P.’s
Current Report on Form 8-K filed September 13, 2012 (File No. 1-12202)).
4.21
Second Supplemental Indenture, dated September 25, 2006, among ONEOK Partners, L.P., ONEOK
Partners Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 6.15
percent Senior Notes due 2016 (incorporated by reference to Exhibit 4.3 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed September 26, 2006 (File No. 1-12202)).
4.22
Third Supplemental Indenture, dated September 25, 2006, among ONEOK Partners, L.P., ONEOK
Partners Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 6.65
percent Senior Notes due 2036 (incorporated by reference to Exhibit 4.4 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed September 26, 2006 (File No. 1-12202)).
4.23
Fourth Supplemental Indenture, dated September 28, 2007, among ONEOK Partners, L.P., ONEOK
Partners Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 6.85
percent Senior Notes due 2037 (incorporated by reference to Exhibit 4.2 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed September 28, 2007 (File No. 1-12202)).
4.24
Fifth Supplemental Indenture, dated March 3, 2009, among ONEOK Partners, L.P., ONEOK Partners
Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 8.625 percent
Senior Notes due 2019 (incorporated by reference to Exhibit 4.2 to ONEOK Partner, L.P.’s Current Report
on Form 8-K filed March 3, 2009 (File No. 1-12202)).
4.25
Ninth Supplemental Indenture, dated September 13, 2012, among ONEOK Partners, L.P., ONEOK Partners
Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 3.375 percent
Senior Notes due 2022 (incorporated by reference from Exhibit 4.3 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed September 13, 2012 (File No. 1-12202)).
4.26Form of Class B unit certificate of ONEOK Partners, L.P. (incorporated by reference to Exhibit 4.1 to
Northern Border Partners, L.P.’s Current Report on Form 8-K filed April 12, 2006 (File No. 1-12202)).
Table of contents

4.27Sixth Supplemental Indenture, dated January 26, 2011, among ONEOK Partners, L.P., ONEOK Partners
Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 3.250 percent
Senior Notes due 2016 (incorporated by reference from Exhibit 4.2 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed January 26, 2011 (File No. 1-12202)).
4.28Seventh Supplemental Indenture, dated January 26, 2011, among ONEOK Partners, L.P., ONEOK Partners
Intermediate Limited Partnership and Wells Fargo Bank, N.A., as trustee, with respect to the 6.125 percent
Senior Notes due 2041 (incorporated by reference from Exhibit 4.3 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed January 26, 2011 (File No. 1-12202)).
4.29
Indenture, dated January 26, 2012, among ONEOK, Inc. and U.S. Bank National Association, as
trustee (incorporated by reference to Exhibit 4.1 to ONEOK, Inc.’s Current Report on Form 8-K filed
January 26, 2012 (File No. 1-13643)).
4.30First Supplemental Indenture, dated January 26, 2012, among ONEOK, Inc. and U.S. Bank National
Association, as trustee, with respect to the 4.25 percent Senior Notes due 2022 (incorporated by reference to
Exhibit 4.2 to ONEOK, Inc.’s Current Report on Form 8-K filed January 26, 2012 (File No. 1-13643)).
4.31
Second Supplemental Indenture, dated August 21, 2015, between ONEOK, Inc. and U.S. Bank National
Association, as trustee, with respect to the 7.50 percent Notes due 2023 (incorporated by reference to
Exhibit 4.1 to ONEOK, Inc.’s Current Report on Form 8-K filed August 21, 2015 (File No. 1-13643)).

10
ONEOK, Inc. Long-Term Incentive Plan (incorporated by reference from Exhibit 10(a) to ONEOK, Inc.’s
Annual Report on Form 10-K for the fiscal year ended December 31, 2001, filed March 14, 2002 (File No.
1-13643).
10.1
ONEOK, Inc. Stock Compensation Plan for Non-Employee Directors (incorporated by reference from
Exhibit 99 to ONEOK, Inc.’s Registration Statement on Form S-8 filed January 25, 2001 (File No.
333-54274)).
10.2
ONEOK, Inc. Supplemental Executive Retirement Plan terminated and frozen December 31, 2004
(incorporated by reference from Exhibit 10.1 to ONEOK, Inc.’s Current Report on Form 8-K filed
December 20, 2004 (File No. 1-13643)).
10.3
ONEOK, Inc. 2005 Supplemental Executive Retirement Plan, as amended and restated, dated December 18,
2008 (incorporated by reference from Exhibit 10.3 to ONEOK, Inc.’s Annual Report on Form 10-K for the
fiscal year ended December 31, 2008, filed February 25, 2009 (File No. 1-13643)).
10.4Not used.
10.5
Form of Indemnification Agreement between ONEOK, Inc. and ONEOK, Inc. officers and directors, as
amended (incorporated by reference from Exhibit 10.5 to ONEOK, Inc.'s Annual Report on Form 10-K for
the fiscal year ended December 31, 2014, filed February 25, 2015 (File No. 1-13643)).
10.6
Amended and Restated ONEOK, Inc. Annual Officer Incentive Plan (incorporated by reference from Exhibit
10.1 to ONEOK, Inc.’s Current Report on Form 8-K filed May 27, 2009 (File No. 1-13643)).
10.7
ONEOK, Inc. Employee Nonqualified Deferred Compensation Plan, as amended and restated December 16,
2004 (incorporated by reference from Exhibit 10.3 to ONEOK, Inc.’s Current Report on Form 8-K filed
December 20, 2004 (File No. 1-13643)).
10.8
ONEOK, Inc. 2005 Nonqualified Deferred Compensation Plan, as amended and restated, dated December
18, 2008 (incorporated by reference from Exhibit 10.8 to ONEOK, Inc.’s Annual Report on Form 10-K for
the fiscal year ended December 31, 2008, filed February 25, 2009 (File No. 1-13643)).
Table of contents

10.9
ONEOK, Inc. Deferred Compensation Plan for Non-Employee Directors, as amended and restated, dated
December 18, 2008 (incorporated by reference from Exhibit 10.9 to ONEOK, Inc.’s Annual Report on
Form 10-K for the fiscal year ended December 31, 2008, filed February 25, 2009 (File No. 1-13643)).
10.10Not used.
10.11
Equity Distribution Agreement, dated November 19, 2014, among ONEOK Partners, L.P., Citigroup Global
Markets Inc., Barclays Capital Inc., Merrill Lynch, Pierce, Fenner & Smith Incorporated, Deutsche Bank
Securities Inc., Goldman, Sachs & Co., Jefferies LLC, J.P. Morgan Securities LLC, Morgan Stanley & Co.
LLC, Mitsubishi UFJ Securities (USA), Inc., RBC Capital Markets, LLC, UBS Securities LLC and Wells
Fargo Securities, LLC (incorporated by reference to Exhibit 1.1 to ONEOK Partners, L.P.’s Current Report
on Form 8-K filed November 19, 2014 (File No. 1-12202)).
10.12Not used.
10.13
Amended and Restated Limited Liability Company Agreement of Overland Pass Pipeline Company LLC
entered into between ONEOK Overland Pass Holdings, L.L.C. and Williams Field Services Company, LLC
dated May 31, 2006 (incorporated by reference to Exhibit 10.6 to ONEOK Partners, L.P.’s Quarterly Report
on Form 10-Q for the quarter ended June 30, 2006, filed August 4, 2006 (File No. 1-12202)).
10.14Form of ONEOK, Inc. Officer Change in Control Severance Plan (incorporated by reference from Exhibit
10.1 to ONEOK, Inc.’s Current Report on Form 8-K filed July 22, 2011 (File No. 1-13643)).
10.15Not used.
10.16Not used.
10.17
Form of Restricted Unit Stock Bonus Award Agreement, as amended and restated effective February 20,
2013 (incorporated by reference to Exhibit 10.1 to ONEOK, Inc.’s Form 8-K filed February 22, 2013 (File
No. 1-13643)).
10.18
Form of Performance Unit Award Agreement, as amended and restated effective February 20, 2013
(incorporated by reference to Exhibit 10.2 to ONEOK, Inc.’s Form 8-K filed February 22, 2013 (File No.
1-13643)).
10.19Form of 2017 Restricted Unit Stock Bonus Award Agreement dated February 22, 2017
10.20Form of 2017 Performance Unit Award Agreement dated February 22, 2017.
10.21
Term Loan Agreement, dated as of January 8, 2016, among ONEOK Partners, L.P., Mizuho Bank, Ltd., as
administrative agent and a lender, and the other lenders parties thereto (incorporated by reference to Exhibit
10.1 to ONEOK, Inc.’s Current Report on Form 8-K filed on January 12, 2016 (File No. 1-13643)).
10.22
Guaranty Agreement, dated as of January 8, 2016, by ONEOK Partners Intermediate Limited Partnership in
favor of Mizuho Bank, Ltd., as administrative agent, under the above-referenced Term Loan Agreement
(incorporated by reference to Exhibit 10.2 to ONEOK, Inc.’s Current Report on Form 8-K filed on January
12, 2016 (File No. 1-13643)).
10.23Not used.
10.24Not used.
10.25
Letter Agreement between ONEOK, Inc. and John W. Gibson, dated as of December 9, 2013 (incorporated
by reference to Exhibit 10.1 to ONEOK, Inc.’s Current Report on Form 8-K filed December 10, 2013
(File No. 1-13643)).
Table of contents

   
 10.26Not used.
10.27Not used.
10.284.14
   
 10.294.15
   
 10.30Not used.
10.314.16
   
 10.324.17
4.18
4.19
4.20
4.21
4.22
4.23
4.24

4.25
   
 10.334.26
10.34
Amendment No. 3 to Third Amended and Restated Agreement of Limited Partnership of ONEOK Partners,
L.P. (incorporated by reference to Exhibit 3.14.3 to ONEOK Partners, L.P.’s Current Report on Form 8-K filed
February 17, 2012 January 26, 2011 (File No. 1-12202)).
   
 10.354.27
Form of 2013 Additional Restricted Unit Stock Bonus Award Agreement, effective February 19, 2014
   
 10.364.28
   
 10.374.29
   
 10.384.30
   
 10.394.31Not used.
   
 10.404.32Not used.
4.33
4.34
4.35
4.36
Table of contents

   
 10.41Not used.
10.424.37
   
 10.434.38
Amended and Restated Credit Agreement, effective asDescription of January 31, 2014, among ONEOK Partners, L.P.,
   
 10.4410
Guaranty Agreement, dated as of January 31, 2014, by ONEOK Partners Intermediate Limited Partnership in
favor of Citibank, N.A., as administrative agent, under the above-referenced Amended and Restated
Credit Agreement (incorporated by reference to Exhibit 10.2 to ONEOK Partners, L.P.’s Quarterly Report on
Form 10-Q for the period ended March 31, 2014, filed May 7, 2014 (File No. 1-12202)).
10.45
10.46
Tax Matters Agreement, dated as of January 14, 2014, by and between ONE Gas, Inc. and ONEOK, Inc.
(incorporated by reference to Exhibit 10.1 to ONEOK, Inc.’s Current Report on Form 8-K filed January 15,
2014 (File No. 1-13643)).
10.47
Transition Services Agreement, dated January 14, 2014, by and between ONE Gas, Inc. and ONEOK, Inc.
(incorporated by reference to Exhibit 10.2 to ONEOK, Inc.’s Current Report on Form 8-K filed January 15,
2014 (File No. 1-13643)).
10.48
Employee Matters Agreement, dated January 14, 2014, by and between ONE Gas, Inc. and ONEOK, Inc.
(incorporated by reference to Exhibit 10.3 to ONEOK, Inc.’s Current Report on Form 8-K filed January 15,
2014 (File No. 1-13643)).
10.49Not used.
10.50Not used.
10.51
Amendment No. 1 to Third Amended and Restated Agreement of Limited Partnership of ONEOK Partners,
L.P., dated July 20, 2007 (incorporated by reference to Exhibit 3.1 to ONEOK Partners, L.P.’s Quarterly
Report on Form 10-Q for the quarter ended June 30, 2007, filed August 3, 2007 (File No. 1-12202)).
10.52
Amendment No. 2 to Third Amended and Restated Agreement of Limited Partnership of ONEOK Partners,
L.P., dated July 12, 2011 (incorporated by reference to Exhibit 3.1 to ONEOK Partners, L.P.’s Current
Report on Form 8-K filed July 13, 2011 (File No. 1-12202)).
10.53
Amendment No. 1 to Third Amended and Restated Limited Liability Company Agreement of ONEOK
Partners GP, L.L.C. effective July 14, 2009 (incorporated by reference to Exhibit 10.1 to ONEOK Partners,
L.P.’s Current Report on Form 8-K filed February 17, 2012 (File No. 1-12202)).
10.54
Form of 2014 Restricted Unit Award Agreement, effective February 19, 2014 (incorporated by reference to
Exhibit 10.5410(a) to ONEOK, Inc.’s Annual Report on Form 10-K for the fiscal year ended December 31, 2013,
2001, filed FebruaryMarch 14, 2002 (File No. 1-13643).
10.1
10.2
10.3
10.4
10.5
10.6
10.7
10.8
10.9
10.10
Table of contents

   
 10.5510.11
10.12
10.13
10.14
10.15
10.16
10.17
10.18
10.19
10.20
10.21

10.22
10.23
10.24
10.25
10.26
10.27
10.28
10.29
10.30
10.31
10.32
   
 10.5610.33
First Amended and Restated Limited Liability Company Agreement of ONEOK ILP GP, L.L.C. effective
July 14, 2009 (incorporated by reference to Exhibit 99.2 to ONEOK Partners, L.P.’s Current Report on Form
8-K filed July 17, 2009 (File No. 1-12202)).
10.57
   
 10.5810.34

   
 10.5910.35

to Exhibit 10.59 to ONEOK, Inc.’s Annual Report on
10.36
   
 10.6010.37
Form of 2015 Performance Unit Award Agreement, effective February 18, 2015 (incorporated by reference
to Exhibit 10.60 to ONEOK, Inc.’s Annual Report on Form 10-K for the fiscal year ended December 31,
2015, filed February 25, 2015 (File No. 1-13643)).
10.61Not used.
10.62
   
 10.6310.38
   
 10.6410.39
Underwriting Agreement, dated August 18, 2015, between ONEOK, Inc. and Citigroup Global Markets, Inc.,
12
Computation of Ratio of Earnings to Fixed Charges for the years ended December 31, 2016, 2015, 2014,
2013 and 2012.2018 Performance Unit Award Agreement.
   
 21
   
 23
   
 31.1
   
 31.2
   
 32.1
   
Table of contents

 32.2
99.1
Unaudited Pro Forma Condensed Consolidated Financial Statements (incorporated by reference to Exhibit
99.1 to ONEOK, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2014, filed February
25, 2015 (File No. 1-13643)).
99.2
Common Unit Purchase Agreement, dated August 11, 2015, between ONEOK Partners, L.P. and Kayne
Anderson MLP Investment Company, Kayne Anderson Energy Total Return Fund, Inc., Kayne Anderson
Midstream/Energy Fund, Inc., Kayne Anderson Energy Development Company, KA First Reserve, LLC,
Nationwide Mutual Insurance Company, Massachusetts Mutual Life Insurance Company, Kayne Anderson
MLP Fund, L.P., Kayne Anderson Midstream Institutional Fund, L.P., Kayne Anderson Real Assets Fund,
L.P., Kayne Institutional Energy Growth & Income Fund, L.P., Kayne Anderson Capital Income Partners
(QP), L.P., Kayne Anderson Income Partners, L.P., KANTI (QP), L.P., Kayne Anderson Non-Traditional
Investments, L.P., KARBO, L.P. and Kaiser Foundation Hospitals (incorporated by reference to Exhibit 99.1
to ONEOK Partners, L.P.’s Current Report on Form 8-K filed on August 17, 2015 (File No. 1-12202)).
   
 101.INSInline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.
   
 101.SCHInline XBRL Taxonomy Extension Schema DocumentDocument.
   
 101.CALInline XBRL Taxonomy Calculation Linkbase DocumentDocument.
   
 101.DEFInline XBRL Taxonomy Extension Definitions DocumentDocument.
   
 101.LABInline XBRL Taxonomy Label Linkbase DocumentDocument.
   
 101.PREInline XBRL Taxonomy Presentation Linkbase DocumentDocument.
104Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101).


Attached as Exhibit 101 to this Annual Report are the following XBRL-related documents: (i) Document and Entity Information; (ii) Consolidated Statements of Income for the years ended December 31, 2016, 20152019, 2018 and 2014;2017; (iii) Consolidated Statements of Comprehensive Income for the years ended December 31, 2016, 20152019, 2018 and 2014;2017; (iv) Consolidated Balance Sheets at December 31, 20162019 and 2015;2018; (v) Consolidated Statements of Cash Flows for the years ended December 31, 2016, 20152019, 2018 and 2014;2017; (vi) Consolidated Statements of Shareholders’Changes in Equity for the years ended December 31, 2016, 20152019, 2018 and 2014;2017; and (vii) Notes to Consolidated Financial Statements.

We also make available on our website the Interactive Data Files submitted as Exhibit 101 to this Annual Report.


ITEM 16.    FORM 10-K SUMMARY


None.

Table of contents


Signatures


Pursuant to the requirements of Section 13 or 15(d) of the Exchange Act, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.


Date: February 28, 2017 ONEOK, Inc.
 Registrant
   
 
Date: February 25, 2020By:/s/ DerekWalter S. ReinersHulse III
  DerekWalter S. Reiners
Senior Vice President,Hulse III
  Chief Financial Officer, Treasurer and
Executive Vice President, Strategic Planning
and TreasurerCorporate Affairs
(Principal Financial Officer)


Pursuant to the requirements of the Exchange Act, this report has been signed below by the following persons on behalf of the registrant and in the capacities indicated on this 28th25th day of February 2017.2020.


 /s/ John W. Gibson /s/ Terry K. Spencer
 John W. Gibson Terry K. Spencer
 Chairman of the Board President, Chief Executive Officer and
   Director
    
 /s/ DerekWalter S. ReinersHulse III /s/ Sheppard F. Miers IIIMary M. Spears
 DerekWalter S. ReinersHulse III Sheppard F. Miers IIIMary M. Spears
 Senior Vice President,Chief Financial Officer, Treasurer and Vice President and
 Chief Financial Officer and TreasurerExecutive Vice President, Strategic Chief Accounting Officer
Planning and Corporate Affairs
    
 /s/ Brian L. Derksen /s/ Julie H. Edwards
 Brian L. Derksen Julie H. Edwards
 Director Director
    
 /s/ Randall J. LarsonMark W. Helderman /s/ StevenRandall J. MalcolmLarson
Mark W. Helderman Randall J. LarsonSteven J. Malcolm
 Director Director
    
 /s/ Kevin S. McCarthySteven J. Malcolm /s/ Jim W. Mogg
 Kevin S. McCarthySteven J. Malcolm Jim W. Mogg
 Director Director
    
 /s/ Pattye L. Moore /s/ Gary D. Parker
 Pattye L. Moore Gary D. Parker
 Director Director
    
 /s/ Eduardo A. Rodriguez  
 Eduardo A. Rodriguez  
 Director  




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