The Williams Companies, Inc. (WMB) 8-K Introduction to the Unaudited Pro Forma Condensed Financial Statements

Exhibit 99.1

Introduction to the Unaudited Pro Forma Condensed Financial Statements

On July 6, 2017, we completed the sale of Williams Olefins, L.L.C., our former wholly owned subsidiary which owned an 88.46 percent undivided ownership interest in a Geismar, Louisiana, olefins plant and associated complex, for cash proceeds totaling $2.084 billion.

The following unaudited pro forma condensed statement of operations has been developed by applying pro forma adjustments to the historical audited statement of operations of Williams Partners L.P. to reflect the disposition. The following unaudited pro forma condensed statement of operations for the year ended December 31, 2017, has been prepared to give effect to the transaction as if the divestiture had occurred at the beginning of 2017. Our historical condensed consolidated statement of operations has been derived from and should be read together with the historical audited consolidated financial statements and related notes in our Annual Report on Form10-K filed February 22, 2018.

The unaudited pro forma condensed statement of operations is presented for illustrative purposes only to reflect the sale of Williams Olefins, L.L.C. and does not represent what our results of operations would actually have been had the sale occurred on the date noted above, or project our results of operations for any future periods. The pro forma adjustments are based on available information and certain assumptions that management believes are factually supportable and are expected to have a continuing impact on our results of operations. All pro forma adjustments and their underlying assumptions are described more fully in the notes to the unaudited pro forma condensed financial information.

Williams Partners L.P.

Unaudited Pro Forma Condensed Statement of Operations

For the year ended December 31, 2017

($ in millions, exceptper-unit amounts)

	Historical
	Williams Partners L.P.			Pro forma Adjustments			Pro Forma
Revenues:
Service revenues	$	5,292		$	(7	)	$	5,285
Product sales		2,718			(205	)		2,513
Total revenues		8,010			(212	)		7,798
Costs and expenses:
Product costs		2,300			(97	)		2,203
Operating and maintenance expenses		1,562			(50	)		1,512
Depreciation and amortization expenses		1,700			(26	)		1,674
Selling, general, and administrative expenses		610			(14	)		596
Impairment of certain assets		1,156			—			1,156
Gain on sale of Geismar Interest		(1,095	)		1,095			—
Regulatory charges resulting from Tax Reform		674			—			674
Insurance recoveries – Geismar Incident		(9	)		9			—
Other (income) expense – net		79			(8	)		71
Total costs and expenses		6,977			909			7,886
Operating income (loss)		1,033			(1,121	)		(88	)
Equity earnings (losses)		434			—			434
Other investing income (loss) - net		281			—			281
Interest expense		(822	)		—			(822	)
Other income (expense) – net		55			—			55
Income (loss) before income taxes		981			(1,121	)		(140	)
Provision (benefit) for income taxes		6			—			6
Net income (loss)		975			(1,121	)		(146	)
Less: Income (loss) attributable to noncontrolling interests		104			—			104
Net income (loss) attributable to controlling interests	$	871		$	(1,121	)	$	(250	)
Allocation of net income (loss) for calculation of earnings per common unit:
Net income (loss) attributable to controlling interests		871						(250	)
Allocation of net income (loss) to Class B units		15						(5	)
Allocation of net income (loss) to common units		856						(245	)
Basic earnings (loss) per common unit:
Net income (loss) per common unit	$	.90					$	(.26	)
Weighted-average common units outstanding (thousands)		947,171						947,171
Diluted earnings (loss) per common unit:
Net income (loss) per common unit	$	.90					$	(.26	)
Weighted-average common units outstanding (thousands)		947,485						947,171

See accompanying notes.

Note 1. Pro Forma Adjustments

Unaudited Pro Forma Condensed Statement of Operations Adjustments

The pro forma adjustments reflect the removal of the historical results of Williams Olefins, L.L.C. and a gain of $1,095 million recognized upon completion of the sale.