CoreSite Realty 8K Results of Operations and Financial Condition | SEC 22 Feb 13

Exhibit 99.2

Earnings Release and Supplemental Information Quarter Ended December 31, 2012

Table of Contents Overview Earnings Release Company Profile Summary of Financial Data Financial Statements Consolidated Balance Sheets Consolidated Statements of Operations Reconciliations of Net Income to FFO, AFFO and EBITDA Operating Portfolio Operating Properties Leasing Statistics Geographic Diversification and 10 Largest Customers Development Summary and Capital Expenditures Capital Structure Market Capitalization and Debt Summary Interest Summary and Debt Covenants 2013 Guidance Appendix 3 8 10 11 12 13 14 15 17 19 20 21 22 2 18

CORESITE REPORTS FOURTH QUARTER FFO OF $0.42 PER SHARE, UP 23.5% YEAR-OVER-YEAR DENVER, CO – February 22, 2013 CoreSite Realty Corporation (NYSE: COR), provider of powerful, network-dense data center campuses and the CoreSite Mesh, which enable interconnected communities of service providers and enterprises, today announced financial results for the fourth quarter ended December 31, 2012. Quarterly and Subsequent Highlights Reported fourth-quarter funds from operations (“FFO”) of $0.42 per diluted share and unit, representing a 5.0% increase over the prior quarter and a 23.5% increase over the prior-year quarter Reported fourth-quarter revenue of $55.3 million, representing a 2.8% increase over the prior quarter and a 20.0% increase over the prior-year quarter Executed new and expansion data center leases representing $11.6 million of annualized GAAP rent Achieved 11.7% rent growth on signed renewals on a cash basis and 15.6% on a GAAP basis Received net proceeds of $110.6 million from the company’s first preferred stock offering In January 2013, amended its credit facility by converting it to unsecured, expanding availability to $355.0 million from $225.0 million, extending its maturity and lowering the interest rate spread In February 2013, acquired a 283,000 square-foot building on 10 acres of land in Secaucus, New Jersey, for development of a new data center campus (NY2) Increased quarterly dividend by 50% to $0.27 per share Tom Ray, CoreSite’s Chief Executive Officer, commented, “During the fourth quarter we made measurable progress across key objectives. We executed strong sales across our customer verticals and platform, signing new and expansion agreements for turn-key data center (“TKD”) capacity reflecting $8.4 million in annualized GAAP rent plus a pre lease to construct a powered-shell building on our Santa Clara campus. While we typically do not enter into large powered-shell leases, we were pleased to leverage off of an existing land holding to serve a strategic customer and further strengthen our Santa Clara campus as a key North American network and cloud hub.” “We were also pleased to execute upon our first preferred stock offering and recast our line of credit, creating the liquidity to fund our near-term growth objectives,” Mr. Ray continued. “Related, to date in 2013, we acquired a land site to support the development of our NY2 data center in the New York region. We continue to be encouraged by CoreSite’s growth opportunities and our vertical sales and marketing model is gaining momentum. Further, we believe that our platform is increasingly well-positioned to serve performance-sensitive applications and enable our customers to scale their businesses and increase profitability.” Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 3

Financial Results CoreSite reported FFO of $19.7 million attributable to dilutive shares and units for the three months ended December 31, 2012, an increase of 5.7% on a sequential quarter basis and a 25.0% increase over the same quarter of the prior year. On a per diluted share and unit basis, FFO was $0.42 for the three months ended December 31, 2012, as compared to $0.34 per diluted share and unit for the three months ended December 31, 2011. Total operating revenue for the three months ended December 31, 2012 was $55.3 million, a 2.8% increase on a sequential-quarter basis and a 20.0% increase over the same quarter of the prior year. The company reported net income for the three months ended December 31, 2012 of $4.6 million, and net income attributable to common shares of $1.9 million, or $0.09 per diluted share. Sales Activity Fourth-quarter lease commencements totaled 21,372 NRSF and $2.9 million of annualized GAAP rent at a weighted average GAAP rental rate of $137 per NRSF. The fourth quarter rental churn rate was 2.1%. Rental churn is calculated based on the annualized rental revenue of leases terminated in the period compared with total annualized rental revenue at the beginning of the period. We signed renewals with a weighted average GAAP rate of $140 per NRSF, reflecting rent growth increases of 11.7% on a cash basis and 15.6% on a GAAP basis. The $140 per foot renewal rental rate includes the renewal of a lower powered, 9,127 NRSF private suite. Excluding that suite, our renewal rental rate was $158 per square foot. Sales activity in the fourth quarter of 2012 reflects the company’s realignment to a vertical selling model and targeted business strategy. New and expansion data center leases executed in the quarter represent $11.6 million of annualized GAAP rent and 156,704 NRSF. These results include a 101,250 NRSF build-to-suit powered shell lease for a valued and strategic customer at the company’s Santa Clara Campus. TKD bookings totaled $8.4 million, comprised of 55,454 NRSF with a weighted average GAAP rate of $151 per NRSF. Included in our TKD sales is a strategic network-anchor agreement in our Chicago facility reflecting discounted rent on an application that we believe will drive material growth in cross connections over time. Excluding this agreement, our weighted average GAAP rent on TKD sales was $162 per NRSF. Development and Acquisition Activity The company’s recent development and acquisition activities further strengthened the company’s platform. On February 7, 2013, CoreSite acquired a 283,000 square-foot building (“NY2”) on 10 acres of land in Secaucus, New Jersey, and will offer up to 18 critical megawatts of capacity and the flexibility to grow with market demand. CoreSite expects to invest $65.0 million to acquire the facility, develop the powered shell, and complete the initial phase of development consisting of 65,000 square feet of leasable space. The Company anticipates offering turn-key data center space in this facility by the end of the fourth quarter of 2013. This is in addition to the company’s expansion in Northern Virginia and the Santa Clara campus as previously announced. Quarter and Year Ended December 31, 2012 Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 4

CoreSite had 94,650 NRSF of data center space at four key locations under construction as of December 31, 2012. As of the end of the fourth quarter, the Company had incurred $37.0 million of the estimated $50.7 million required to complete the projects. Balance Sheet and Liquidity As of December 31, 2012, CoreSite had $59.8 million of total long-term debt equal to 4.1% of total enterprise value and equal to 0.6x annualized adjusted EBITDA for the quarter ended December 31, 2012. During the fourth quarter of 2012, CoreSite completed a public offering of 4,600,000 shares of 7.25% Series A Cumulative Redeemable Preferred Stock at a price of $25.00 per share for net proceeds of approximately $110.6 million, after deducting underwriting discounts and commissions and expenses. At December 31, 2012, CoreSite had $174.8 million of total long-term debt and preferred stock equal to 11.9% of total enterprise value and equal to 1.8x annualized adjusted EBITDA for the quarter ended December 31, 2012. At quarter end, CoreSite had $8.1 million of cash available on its balance sheet. On January 3, 2013 CoreSite amended and restated its revolving credit facility, which was scheduled to mature on December 15, 2014. The new credit facility is unsecured compared to the prior facility, which was secured by five assets, and the borrowing capacity was increased from $225.0 million to $355.0 million. The facility has a five-year term through January 2018, including a one-year extension option. On January 3, 2013, the company had $346.5 million of available capacity under its revolving credit facility. Dividend On November 26, 2012, CoreSite announced a dividend of $0.27 per share of common stock and common stock equivalents for the fourth quarter of 2012. This dividend represented a $0.09 per share, or 50%, increase from the previous quarterly dividend rate of $0.18 per share. The dividend was paid on January 15, 2013 to shareholders of record on December 31, 2012. 2013 Guidance The annual guidance provided below and on page 21 of our supplemental represents forward-looking projections, which are based on current economic conditions, internal assumptions about our existing customer base and the supply and demand dynamics of the markets in which CoreSite operates. Further, the guidance does not include the impact of any future financing, investment or disposition activities. The company is introducing its 2013 guidance of FFO per diluted share and unit in the range of $1.72 to $1.82. In addition, the company’s estimate of the net income attributable to common shares is $0.37 to $0.47 per diluted share, with the difference between FFO and net income being real estate depreciation and amortization. Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 5 Quarter and Year Ended December 31, 2012

Conference Call Details The company will host a conference call on February 22 at 12:00 p.m. (Eastern Time) to discuss its financial results, current business trends and market conditions. The call will be accessible by dialing +1-877-407-3982 (domestic) or +1-201-493-6780 (international). A replay will be available until March 1, 2013 and can be accessed shortly after the call by dialing +1-877-870-5176 (domestic) or +1-858-384-5517 (international). The passcode for the replay is 407943. The quarterly conference call also will be offered as a simultaneous webcast, accessible by visiting www.coresite.com and clicking on the “Investors” tab. An on-line replay will be available for a limited time immediately following the call. About CoreSite CoreSite Realty Corporation (NYSE: COR) is the data center provider chosen by more than 750 of the world's leading carriers and mobile operators, content and cloud providers, media and entertainment companies, and global enterprises to run their performance-sensitive applications and to connect and do business. CoreSite propels customer growth and long-term competitive advantage through the CoreSite Mesh by connecting the Internet, private networking, mobility, and cloud communities within and across its 14 high-performance data center campuses in nine markets in North America. With direct access to 275+ carriers and ISPs, over 180 leading cloud and IT service providers, inter-site connectivity, and the nation's first Open Cloud Exchange that provides access to thousands of lit buildings and multiple key cloud on-ramps, CoreSite provides easy, efficient and valuable gateways to global business opportunities. For more information, visit www.CoreSite.com. CoreSite Investor Relations Contact +1 303.222.7276 InvestorRelations@CoreSite.com CoreSite Media Contact Jeannie Zaemes | CoreSite Marketing Senior Director +1 720.446.2006 | +1 866.777.CORE Jeannie.Zaemes@CoreSite.com Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 6 Quarter and Year Ended December 31, 2012

Forward Looking Statements This earnings release and accompanying supplemental information may contain forward-looking statements within the meaning of the federal securities laws. Forward-looking statements relate to expectations, beliefs, projections, future plans and strategies, anticipated events or trends and similar expressions concerning matters that are not historical facts. In some cases, you can identify forward-looking statements by the use of forward-looking terminology such as “believes,” “expects,” “may,” “will,” “should,” “seeks,” “approximately,” “intends,” “plans,” “pro forma,” “estimates” or “anticipates” or the negative of these words and phrases or similar words or phrases that are predictions of or indicate future events or trends and that do not relate solely to historical matters. Forward-looking statements involve known and unknown risks, uncertainties, assumptions and contingencies, many of which are beyond CoreSite’s control, that may cause actual results to differ significantly from those expressed in any forward-looking statement. These risks include, without limitation: the geographic concentration of the company’s data centers in certain markets and any adverse developments in local economic conditions or the demand for data center space in these markets; fluctuations in interest rates and increased operating costs; difficulties in identifying properties to acquire and completing acquisitions; significant industry competition; the company’s failure to obtain necessary outside financing; the company’s failure to qualify or maintain its status as a REIT; financial market fluctuations; changes in real estate and zoning laws and increases in real property tax rates; and other factors affecting the real estate industry generally. All forward-looking statements reflect the company’s good faith beliefs, assumptions and expectations, but they are not guarantees of future performance. Furthermore, the company disclaims any obligation to publicly update or revise any forward-looking statement to reflect changes in underlying assumptions or factors, of new information, data or methods, future events or other changes. For a further discussion of these and other factors that could cause the company’s future results to differ materially from any forward-looking statements, see the section entitled “Risk Factors” in the company’s most recent annual report on Form 10-K, and other risks described in documents subsequently filed by the company from time to time with the Securities and Exchange Commission. Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 7 Quarter and Year Ended December 31, 2012

The Company serves over 750 customers across more than two million square feet, including space held for development, and provides access to over 275 network service providers. As of December 31, 2012, the Company updated its nomenclature used to reference its property portfolio. Included below is a reconciliation between the new supplemental nomenclature to the nomenclature found in previous supplementals. Company Profile Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 8

NYSE-traded with a strong balance sheet NYSE: COR (2010); REIT status Predecessor entities founded in 2000 Equity market cap: $1.3 billion at December 31, 2012 Growth capacity: 4.1% debt to enterprise value at December 31, 2012 Company Profile Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 9 Scalable, broad platform in Tier-1 markets 14 operating data centers, 3 data centers under construction 9 top North American markets located in network, financial, cloud and commerce hubs 2+ million gross square feet Ability to nearly double data center footprint on land and buildings currently owned 300+ employees Dense network connectivity and ecosystems Over 275 network service providers Over 750 customers and 15,000 cross-connects Key ecosystems of customers and partners consisting of 34% networks & mobility, 23% enterprise, 23% cloud & IT service providers, 13% digital content & multimedia, and 7% systems integrators and managed services providers Partner-enabled value-added services supporting cloud computing Product, services & operational excellence Cabinet, standard or custom cage, computer rooms Cross-connects, Any2 Internet Exchange, Cloud Exchange – Ethernet Breakered and metered power Six 9s uptime since 2010

Summary of Financial Data Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix (in thousands, except share, per share and NRSF data) 10 Three Months Ended or As of: December 31, September 30, June 30, March 31, December 31, Summary of Results 2012 2012 2012 2012 2011 Operating revenues $ 55,252 $ 53,762 $ 50,636 $ 47,284 $ 46,029 Net income 4,578 2,947 1,848 1,343 462 Net income attributable to common shares 1,862 1,320 826 600 179 Funds from operations (FFO) attributable to common shares and OP units 19,704 18,636 17,285 16,351 15,769 Adjusted funds from operations (AFFO) 16,169 17,155 16,599 12,714 14,034 Earnings before interest, taxes, depreciation and amortization (EBITDA) 22,272 21,642 19,761 17,695 16,815 Adjusted EBITDA 24,168 23,491 21,701 20,014 17,508 Per share - diluted: Net income attributable to common shares $ 0.09 $0.06 $0.04 $0.03 $0.01 FFO per common share and OP unit $ 0.42 $0.40 $0.37 $0.36 $0.34 Dividend Activity Dividends declared per common share and OP unit $ 0.27 $0.18 $0.18 $0.18 $0.18 FFO payout ratio 64% 45% 48% 51% 53% Operating Portfolio Statistics Operating data center properties 14 14 14 12 12 Operating data center NRSF 1,208,365 1,196,571 1,193,321 1,105,180 1,058,878 Data center NRSF leased 930,245 922,018 889,288 899,322 878,395 Data center % leased 77.0% 77.1% 74.5% 81.4% 83.0% Office and light industrial NRSF 374,304 374,260 419,060 419,060 417,864 Office and light industrial NRSF leased 293,495 293,519 323,866 344,955 340,111 Office and light industrial % leased 78.4% 78.4% 77.3% 82.3% 81.4% Market Capitalization, Debt & Preferred Stock Total enterprise value $ 1,462,710 $ 1,406,509 $ 1,346,769 $ 1,221,002 $ 943,547 Total debt outstanding 59,750 154,365 146,449 132,032 121,864 Total debt and preferred stock outstanding 174,750 154,365 146,449 132,032 121,864 Debt to: Enterprise value 4.1% 11.0% 10.9% 10.8% 12.9% Adjusted EBITDA 0.6x 1.6x 1.7x 1.6x 1.7x Undepreciated book value of total assets 6.3% 16.8% 16.3% 14.9% 14.0% Debt & Preferred Stock to: Enterprise value 11.9% 11.0% 10.9% 10.8% 12.9% Adjusted EBITDA 1.8x 1.6x 1.7x 1.6x 1.7x Undepreciated book value of total assets 18.4% 16.8% 16.3% 14.9% 14.0% Weighted Average Shares and Units Common shares - basic 20,607,119 20,554,893 20,532,930 20,455,875 19,988,150 Operating partnership units - basic 25,353,709 25,346,805 25,346,097 25,345,082 25,780,217 Total common shares and OP units - basic 45,960,828 45,901,698 45,879,027 45,800,957 45,768,367 Shares issued from assumed conversion of restricted shares/options 429,675 472,742 381,756 238,980 93,853 Total common shares and OP units - diluted 46,390,503 46,374,440 46,260,783 46,039,937 45,862,220

Consolidated Balance Sheets Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix (in thousands) 11 December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 Operating revenues $ 55,252 $ 53,762 $ 50,636 $ 47,284 $ 46,029 Net income 4,578 2,947 1,848 1,343 462 Net income attributable to common shares 1,862 1,320 826 600 179 Funds from operations (FFO) attributable to common shares and OP units 19,704 18,636 17,285 16,351 15,769 Adjusted funds from operations (AFFO) 16,169 17,155 16,599 12,714 14,034 Earnings before interest, taxes, depreciation and amortization (EBITDA) 22,272 21,642 19,761 17,695 16,815 Adjusted EBITDA 24,168 23,491 21,701 20,014 17,508 Per share - diluted: Net income attributable to common shares $ 0.09 $0.06 $0.04 $0.03 $0.01 FFO per common share and OP unit $ 0.42 $0.40 $0.37 $0.36 $0.34 Dividend Activity Dividends declared per common share and OP unit $ 0.27 $0.18 $0.18 $0.18 $0.18 FFO payout ratio 64% 45% 48% 51% 53% Operating Portfolio Statistics Operating data center properties 14 14 14 12 12 Operating data center NRSF 1,208,365 1,196,571 1,193,321 1,105,180 1,058,878 Data center NRSF leased 930,245 922,018 889,288 899,322 878,395 Data center % leased 77.0% 77.1% 74.5% 81.4% 83.0% Office and light industrial NRSF 374,304 374,260 419,060 419,060 417,864 Office and light industrial NRSF leased 293,495 293,519 323,866 344,955 340,111 Office and light industrial % leased 78.4% 78.4% 77.3% 82.3% 81.4% Market Capitalization, Debt & Preferred Stock Total enterprise value $ 1,462,710 $ 1,406,509 $ 1,346,769 $ 1,221,002 $ 943,547 Total debt outstanding 59,750 154,365 146,449 132,032 121,864 Total debt and preferred stock outstanding 174,750 154,365 146,449 132,032 121,864 Debt to: Enterprise value 4.1% 11.0% 10.9% 10.8% 12.9% Adjusted EBITDA 0.6x 1.6x 1.7x 1.6x 1.7x Undepreciated book value of total assets 6.3% 16.8% 16.3% 14.9% 14.0% Debt & Preferred Stock to: Enterprise value 11.9% 11.0% 10.9% 10.8% 12.9% Adjusted EBITDA 1.8x 1.6x 1.7x 1.6x 1.7x Undepreciated book value of total assets 18.4% 16.8% 16.3% 14.9% 14.0% Weighted Average Shares and Units Common shares - basic 20,607,119 20,554,893 20,532,930 20,455,875 19,988,150 Operating partnership units - basic 25,353,709 25,346,805 25,346,097 25,345,082 25,780,217 Total common shares and OP units - basic 45,960,828 45,901,698 45,879,027 45,800,957 45,768,367 Shares issued from assumed conversion of restricted shares/options 429,675 472,742 381,756 238,980 93,853 Total common shares and OP units - diluted 46,390,503 46,374,440 46,260,783 46,039,937 45,862,220

Consolidated Statements of Operations (in thousands, except share and per share data) Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 12 Three Months Ended: December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 Operating revenues: Rental revenue $ 31,979 $ 31,461 $ 30,464 $ 29,493 $ 29,064 Power revenue 14,119 14,204 12,910 12,330 11,411 Interconnection revenue 6,155 5,955 5,244 3,533 3,273 Tenant reimbursement and other 2,999 2,142 2,018 1,928 2,281 Total operating revenues 55,252 53,762 50,636 47,284 46,029 Operating expenses: Property operating and maintenance 15,206 16,360 15,274 14,395 15,063 Real estate taxes and insurance 2,461 2,158 2,132 2,014 2,064 Depreciation and amortization 16,336 16,583 15,947 15,461 15,743 Sales and marketing 3,389 2,231 2,581 2,129 1,619 General and administrative 7,133 6,389 6,036 6,352 5,880 Rent 4,754 4,689 4,691 4,577 4,588 Transaction costs 37 293 161 122 - Total operating expenses 49,316 48,703 46,822 45,050 44,957 Operating income 5,936 5,059 3,814 2,234 1,072 Interest income 1 5 5 2 2 Interest expense (1,314) (1,595) (1,309) (1,018) (838) Income before income taxes 4,623 3,469 2,510 1,218 236 Income tax (expense) benefit (45) (522) (662) 125 226 Net income 4,578 2,947 1,848 1,343 462 Net income attributable to noncontrolling interests 2,276 1,627 1,022 743 283 Net income attributable to CoreSite Realty Corporation 2,302 1,320 826 600 179 Preferred dividends (440) - - - - Net income attributable to common shares $ 1,862 $ 1,320 $ 826 $ 600 $ 179 Net income per share attributable to common shares: Basic $ 0.09 $ 0.06 $ 0.04 $ 0.03 $ 0.01 Diluted $ 0.09 $ 0.06 $ 0.04 $ 0.03 $ 0.01 Weighted average common shares outstanding: Basic 20,607,119 20,554,893 20,532,930 20,455,875 19,988,150 Diluted 21,036,794 21,027,635 20,914,686 20,694,855 20,082,003

Reconciliations of Net Income to FFO, AFFO and EBITDA (in thousands, except share and per share data) Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 13 Reconciliation of Net Income available to FFO Three Months Ended: December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 Net income $ 4,578 $ 2,947 $ 1,848 $ 1,343 $ 462 Real estate depreciation and amortization 15,566 15,689 15,437 15,008 15,307 FFO $ 20,144 $ 18,636 $ 17,285 $ 16,351 $ 15,769 Preferred stock dividends (440) - - - - FFO available to common shareholders and OP unitholders $ 19,704 $ 18,636 $ 17,285 $ 16,351 $ 15,769 Weighted average common shares and OP units outstanding - diluted 46,390,503 46,374,440 46,260,783 46,039,937 45,862,220 FFO per common share and OP unit - diluted $ 0.42 $ 0.40 $ 0.37 $ 0.36 $ 0.34 Reconciliation of FFO to AFFO Three Months Ended: December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 FFO available to common shareholders and unitholders $ 19,704 $ 18,636 $ 17,285 $ 16,351 $ 15,769 Adjustments: Amortization of deferred financing costs 374 435 436 436 371 Non-cash compensation 1,568 1,556 1,779 747 693 Non-real estate depreciation 770 894 510 453 436 Straight-line rent adjustment (720) (734) (825) (1,318) (1,055) Amortization of above and below market leases (264) (444) (401) (396) (511) Recurring capital expenditures (2,064) (822) (622) (566) (42) Tenant improvements (278) (1,362) (1,001) (1,015) (1,058) Capitalized leasing commissions (2,921) (1,004) (562) (1,978) (569) AFFO available to common shareholders and OP unitholders $ 16,169 $ 17,155 $ 16,599 $ 12,714 $ 14,034 Reconciliation of Net Income to EBITDA and Adjusted EBITDA Three Months Ended: December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 Net income $ 4,578 $ 2,947 $ 1,848 $ 1,343 $ 462 Adjustments: Interest expense, net of interest income 1,313 1,590 1,304 1,016 836 Income taxes 45 522 662 (125) (226) Depreciation and amortization 16,336 16,583 15,947 15,461 15,743 EBITDA $ 22,272 $ 21,642 $ 19,761 $ 17,695 $ 16,815 Non-cash compensation 1,568 1,556 1,779 747 693 Transaction costs / litigation settlement expenses 328 293 161 1,572 - Adjusted EBITDA $ 24,168 $ 23,491 $ 21,701 $ 20,014 $ 17,508

Operating Properties (in thousands, except NRSF data) Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 14 Operating NRSF(1) Office and Light- Data Center(2) Industrial(3) Total Development(7) Annualized Rent Percent Percent Percent Total Market/Facilities ($000)(4 ) Total Leased(5) Total Total Leased(5) Total(6 ) Leased(5) Total Portfolio Los Angeles LA1* $ 24,403 150,278 76.7 % 7,500 45.5 % 157,778 75.2 % 7,309 165,087 LA2 12,327 159,617 75.3 8,360 33.7 167,977 73.3 266,183 434,160 Los Angeles Total 36,730 309,895 76.0 15,860 39.3 325,755 74.2 273,492 599,247 San Francisco Bay SV1 11,277 84,045 88.4 206,255 80.2 290,300 82.6 - 290,300 SV2 5,968 76,676 66.4 - - 76,676 66.4 - 76,676 Santa Clara Campus 15,735 119,067 68.4 71,196 91.7 190,263 77.1 305,987 496,250 San Francisco Bay Total 32,980 279,788 79.5 277,451 83.2 557,239 78.5 305,987 863,226 Northern Virginia VA1 20,888 201,719 72.4 61,050 76.4 262,769 73.3 - 262,769 VA2 - - - - - - - 198,000 198,000 DC1* 2,028 22,137 74.8 - - 22,137 74.8 - 22,137 Northern Virginia Total 22,916 223,856 72.6 61,050 76.4 284,906 73.4 198,000 482,906 Boston BO1 9,955 148,795 92.5 13,063 39.3 161,858 88.2 111,313 273,171 Chicago CH1 9,834 158,167 82.5 4,946 56.9 163,113 81.7 20,240 183,353 New York NY1* 5,088 48,404 69.1 - - 48,404 69.1 - 48,404 NY2 - - - - - - - 283,000 283,000 New York Total 5,088 48,404 69.1 - - 48,404 69.1 283,000 331,404 Miami MI1 1,724 30,176 56.3 1,934 100.0 32,110 58.9 13,154 45,264 Denver DE1* 766 4,144 93.4 - - 4,144 93.4 - 4,144 DE2* 172 5,140 61.3 - - 5,140 61.3 - 5,140 Denver Total 938 9,284 75.7 - - 9,284 75.7 - 9,284 Total Facilities $ 120,165 1,208,365 77.0 % 374,304 78.4 % 1,582,669 77.3 % 1,205,186 2,787,855 * Indicates properties in which we hold a leasehold interest. (1) Represents the square feet at each building under lease as specified in existing customer lease agreements plus management’s estimate of space available for lease to customers based on engineers’ drawings and other factors, including required data center support space (such as mechanical, telecommunications and utility rooms) and building common areas. Total NRSF at a given facility includes the total operating NRSF and total development NRSF, but excludes our office space at a facility and our corporate headquarters. (2) Represents the NRSF at each operating facility that is currently leased or readily available for lease as data center space. Both leased and available data center NRSF includes a factor to account for a customer’s proportionate share of the required data center support space (such as the mechanical, telecommunications and utility rooms) and building common areas, which may be updated on a periodic basis to reflect the most current build-out of our properties. (3) Represents the NRSF at each operating facility that is currently leased or readily available for lease as space other than data center space, which is typically space offered for office or light-industrial uses. (4) Represents the monthly contractual rent under existing customer leases as of December 31, 2012, multiplied by 12. This amount reflects total annualized base rent before any one-time or non-recurring rent abatements and it excludes operating expense reimbursement, power revenue and interconnection revenue. (5) Includes customer leases that have commenced as of December 31, 2012. The percent leased is determined based on leased square feet as a proportion of total operating NRSF. The percent leased for data center space, office and light industrial space, and space in total would have been 81.3%, 78.8%, and 80.8%, respectively, if all leases signed in current and prior periods had commenced. (6) Represents the NRSF at an operating facility currently leased or readily available for lease. This excludes existing vacant space held for development. (7) Represents vacant space and entitled land in our portfolio that require significant capital investment in order to develop into data center facilities as of December 31, 2012, with the exception of NY2, which was acquired February 7, 2013. Includes NRSF under construction for which substantial activities are ongoing to prepare the property for its intended use following development. Total development NRSF and total operating NRSF represent the total NRSF at a given facility.

Leasing Statistics Data Center Leasing Activity Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 15 GAAP GAAP Leasing Number Total Annualized Annualized Rental Cash GAAP Activity of Leased Rent per Rent Churn Rent Rent Period Leases(1) NRSF(2) Leased NRSF (000's) Rate(3) Growth(4) Growth(4) New/expansion leases commenced FY 2012 336 109,059 $ 179 $ 19,475 FY 2011 328 142,734 153 21,881 Q4 2012 100 21,372 $ 137 $ 2,924 Q3 2012 92 39,991 146 5,851 Q2 2012 83 16,998 195 3,315 Q1 2012 61 30,698 241 7,385 Q4 2011 72 38,864 168 6,530 New/expansion leases signed FY 2012 339 231,944 $ 109 (5) $ 25,301 FY 2011 328 138,061 163 22,526 Q4 2012 100 156,704 $ 74 (5) $ 11,583 Q3 2012 77 11,387 177 2,012 Q2 2012 95 26,290 177 4,649 Q1 2012 67 37,563 188 7,057 Q4 2011 64 35,461 192 6,802 Renewal leases commenced FY 2012 267 150,038 $ 128 $ 19,269 8.5% 6.0% 12.1% FY 2011 264 108,239 148 15,976 7.9% 17.1% 27.5% Q4 2012 50 52,225 $ 140 $ 7,323 2.1% 11.7% 15.6% Q3 2012 69 18,332 164 3,012 1.1% 4.0% 9.1% Q2 2012 81 64,048 99 6,310 3.9% 1.0% 9.2% Q1 2012 67 15,433 170 2,624 1.4% 3.3% 12.5% Q4 2011 42 22,911 133 3,047 4.0% -2.8% 4.8%

Leasing Statistics Lease Distribution Lease Expirations (total operating properties) Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 16 Total Annualized Number Operating Percentage Percentage Annualized Annualized Rent Per of NRSF of of Total Annualized of Rent Per Rent at Leased Leases Expiring Operating Rent Annualized Leased Expiration NRSF at Year of Lease Expiration Expiring(1) Leases NRSF ($000)(2) Rent NRSF(3) ($000)(4) Expiration(5) Available as of December 31, 2012(6) - 358,929 22.7 % $ - - % $ - $ - $ - 2013 601 254,034 16.1 29,372 24.5 115.62 29,735 117.05 2014(7) 279 300,278 19.0 29,561 24.6 98.45 30,453 101.42 2015 201 103,625 6.5 16,943 14.1 163.50 19,597 189.11 2016 99 167,444 10.6 12,965 10.8 77.43 14,438 86.23 2017 95 126,045 8.0 14,739 12.3 116.93 20,202 160.28 2018 11 93,341 5.9 9,028 7.5 96.72 11,693 125.27 2019 3 80,708 5.1 1,615 1.3 20.01 1,788 22.15 2020 4 30,664 1.9 1,099 0.9 35.84 1,194 38.94 2021 9 18,155 1.1 1,980 1.6 109.06 2,876 158.41 2022 8 26,132 1.6 2,334 1.9 89.32 3,839 146.91 2023-Thereafter 5 23,314 1.5 529 0.5 22.69 661 28.35 Portfolio Total / Weighted Average 1,315 1,582,669 100.0 % $ 120,165 100.0 % $ 98.19 $ 136,476 $ 111.52 (1) Includes leases that upon expiration will automatically be renewed, primarily on a month-to-month basis. Number of leases represents each agreement with a customer; a lease agreement could include multiple spaces and a customer could have multiple leases. (2) Represents the monthly contractual rent under existing customer leases as of December 31, 2012, multiplied by 12. This amount reflects total annualized base rent before any one-time or non-recurring rent abatements and excludes operating expense reimbursement, power revenue and interconnection revenue. (3) Annualized rent as defined above, divided by the square footage of leases expiring in the given year. (4) Represents the final monthly contractual rent under existing customer leases as of December 31, 2012, multiplied by 12. This amount reflects total annualized base rent before any one-time or non-recurring rent abatements and it excludes operating expense reimbursement, power revenue and interconnection revenue. (5) Annualized rent at expiration as defined above, divided by the square footage of leases expiring in the given year. This metric reflects the rent growth inherent in the existing base of lease agreements. (6) Excludes NRSF held for development or under construction. (7) Includes an office lease, which is an interim lease in place that expires on May 31, 2014. Upon the expiration of the interim lease and the substantial completion of tenant improvements by us, a new lease that has already been executed by both parties will commence. The new lease includes 119,729 NRSF with a ten-year term and a termination option at the end of year eight. Total Percentage Percentage Number Percentage Operating of Total Annualized of of of All NRSF of Operating Rent Annualized Square Feet Under Lease(1) Leases(2) Leases Leases(3) NRSF ($000)(4) Rent Available colocation(5) - - % 278,120 17.6 % $ - - % Available office and light-industrial - - 80,809 5.1 - - Colocation NRSF Under Lease 1,000 or less 1,145 87.1 181,101 11.4 34,336 28.6 1,001 - 2,000 47 3.6 67,445 4.3 9,512 7.9 2,001 - 5,000 69 5.2 210,537 13.3 24,580 20.5 5,001 - 10,000 20 1.5 139,963 8.9 14,694 12.2 10,001 - 25,000 9 0.6 139,256 8.8 19,984 16.6 Greater than 25,000 2 0.2 61,614 3.9 6,614 5.5 Powered Shell 6 0.5 166,738 10.5 4,534 3.8 Office and light-industrial(6) 17 1.3 257,086 16.2 5,911 4.9 Portfolio Total 1,315 100.0 1,582,669 100.0 % $ 120,165 100.0 (1) Represents all leases in our portfolio, including data center and office and light-industrial leases. (2) Includes leases that upon expiration will automatically be renewed, primarily on a month-to-month basis. Number of leases represents each agreement with a customer; a lease agreement could include multiple spaces and a customer could have multiple leases. (3) Represents the square feet at a building under lease as specified in the lease agreements plus management’s estimate of space available for lease to third parties based on engineers' drawings and other factors, including required data center support space (such as mechanical, telecommunications and utility rooms) and building common areas. (4) Represents the monthly contractual rent under existing customer leases as of December 31, 2012, multiplied by 12. This amount reflects total annualized base rent before any one-time or non-recurring rent abatements and excludes operating expense reimbursement, power revenue and interconnection revenue. (5) Excludes NRSF held for development or under construction. (6) Excludes office and light-industrial space of 36,409 NRSF that is a component of colocation leases. The 36,409 NRSF of office and light- industrial space is leased to data center tenants as incremental space to their data center lease space.

Geographic Diversification and 10 Largest Customers 10 Largest Customers Geographic Diversification Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 17 Percentage of Total Metropolitan Market Annualized Rent Los Angeles 30.6 % San Francisco Bay 27.4 Northern Virginia 19.1 Boston 8.3 Chicago 8.2 New York 4.2 Miami 1.4 Denver 0.8 Total 100 % As of December 31, 2012, our portfolio was leased to over 750 companies, many of which are globally recognized firms. The following table sets forth information regarding the ten largest customers in our portfolio based on annualized rent as of December 31, 2012: Weighted Percentage Percentage Average Number Total of Total Annualized of Remaining of Leased Operating Rent Annualized Lease Term in Customer Industry CoreSite Vertical Locations NRSF(1) NRSF(2) ($000)(3) Rent(4) Months(5) 1 Technology Digital Content & Multimedia 2 50,625 3.2 % $ 9,461 7.9 % 46 Systems Integrators & Managed - 2 Technology 3 52,902 3.3 6,362 5.3 56 --Services Providers 3 Technology Digital Content & Multimedia 7 38,992 2.5 4,526 3.8 11 4 Government*(6) Enterprises 1 141,774 9.0 4,011 3.3 22 5 Technology Cloud & IT Service Providers 1 26,842 1.7 3,494 2.9 64 Systems Integrators & Managed - 6 Technology 1 6,034 0.4 2,495 2.1 25 --Services Providers 7 Government Enterprises 2 16,266 1.0 2,271 1.9 21 8 Telecommunications Network & Mobility 3 18,562 1.2 1,943 1.6 82 9 Technology Cloud & IT Service Providers 3 9,719 0.6 1,883 1.6 8 10 Financial Enterprises 2 11,670 0.7 1,856 1.5 26 Total/Weighted Average 373,386 23.6 % $ 38,302 31.9 % 39 * Denotes customer using space for general office purposes. (1) Total leased NRSF is determined based on contractually leased square feet for leases that have commenced on or before December 31, 2012. We calculate occupancy based on factors in addition to contractually leased square feet, including required data center support space (such as the mechanical, telecommunications and utility rooms) and building common areas. (2) Represents the customer’s total leased square feet divided by the total operating NRSF in the portfolio which, as of December 31, 2012, consisted of 1,582,669 NRSF. (3) Represents the monthly contractual rent under existing customer leases as of December 31, 2012, multiplied by 12. This amount reflects total annualized base rent before any one-time or non-recurring rent abatements and excludes operating expense reimbursement, power revenue and interconnection revenue. (4) Represents the customer’s total annualized rent divided by the total annualized rent in the portfolio as of December 31, 2012, which was approximately $120.2 million. (5) Weighted average based on percentage of total annualized rent expiring calculated as of December 31, 2012. (6) The data presented represents an interim office space lease in place that expires in May 2014. Upon expiration of the interim lease and the substantial completion of building improvements by us, a new lease that has already been executed by both parties will commence. That lease includes 119,729 NRSF with a ten-year term and a termination option at the end of year eight.

Development Summary and Capital Expenditures Data Center Projects Under Construction as of December 31, 2012 Completed Pre-Stabilized Data Center Projects as of December 31, 2012 Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix (in thousands, except NRSF data) Capital Expenditures – Quarter Ended 18 Percent Projects/Facilities Metropolitan Area Completion NRSF Cost Leased(1) VA1 Northern Virginia Mar 2012 31,290 $13,100 13.3% SV4 San Francisco Bay Mar 2012 15,013 9,700 56.9% VA1 Northern Virginia Jun 2012 28,169 16,240 25.2% CH1 Chicago Jun 2012 29,261 9,770 16.9% SV4 San Francisco Bay Jun 2012 16,835 13,541 61.4% SV4(2) San Francisco Bay Oct 2012 19,103 14,837 0.0% Total completed pre-stabilized(3) 139,671 $ 77,188 25.1% (1) These projects/facilities are included in the operating NRSF information in the Operating Properties table on page 14. (2) Represents pre-sold dedicated built-to-suit space that was completed during the fourth quarter 2012, of which the entire 19,103 NRSF commenced on January 1, 2013. (3) Total completed pre-stabilized percent leased would have been 38.8% if the 19,103 NRSF pre-sold dedicated built-to-suit lease commenced during the quarter. Costs Estimated Incurred to- Estimated Projects/Facilities(2) Metropolitan Area Completion NRSF date Total (1) SV4 San Francisco Bay Q1 2013 31,497 $ 25,641 $ 27,200 LA2 Los Angeles Q1 2013 19,250 6,353 9,600 BO1 Boston Q2 2013 23,663 831 8,700 CH1 Chicago Q2 2013 20,240 4,145 5,200 Total under construction 94,650 $ 36,971 $ 50,700 Planned near-term construction (2)(3) VA2 Northern Virginia Q4 2013 50,000 $ 2,000 $ 60,000 SV5 San Francisco Bay Q4 2013 101,250 505 19,000 NY2(4) New York Q4 2013 65,000 1,127 65,000 Total planned near-term construction 216,250 $ 3,632 $ 144,000 (1) Reflects management's estimate of cost of completion based upon the actual cost as of December 31, 2012, plus management's estimate of the cost to complete construction. (2) NRSF reflects management’s estimate based on engineering drawings and required support space and is subject to change based on final demising of the space. (3) Planned near-term construction is management's best estimate of current planned projects. Projects may be added or deleted from this list at any time based upon management's evaluation of current market demands and economic performance. (4) On February 7, 2013, the Company acquired land and an existing building in Secaucus, New Jersey, referred to as NY2. Management plans to develop approximately 283,000 NRSF of data center space at this property of which 65,000 NRSF is planned near-term construction. December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 Recurring capital expenditures $ 2,064 $ 822 $ 622 $ 566 $ 42 Development capital expenditures 31,986 23,181 16,757 16,052 18,582 Total $ 34,050 $ 24,003 $ 17,379 $ 16,618 $ 18,624

Market Capitalization and Debt Summary Debt Summary (1) Outstanding as of: Market Capitalization Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix (in thousands, except per share data) Debt Maturities 19 Shares or Market Price as of Equivalents December 31, 2012 / Market Value Outstanding Liquidation Value Equivalents Common shares 21,203 $27.66 $ 586,475 Operating partnership units 25,361 $27.66 701,485 Liquidation value of preferred stock 4,600 $25.00 115,000 Total equity 1,402,960 Total debt 59,750 Total enterprise value $ 1,462,710 Total debt to total enterprise value 4.1% Total debt and preferred stock to total enterprise value 11.9% Maturity Interest Maturity Date with December 31, September 30, June 30, March 31, December 31, Instrument Rate(2) Date Extension 2012 2012 2012 2012 2011 SV1 - mortgage loan 3.71% 10/9/2014 $ 59,750 $ 60,000 $ 60,000 $ 60,000 $ 60,000 Senior credit facility(3) 2.21% 1/3/2017 1/3/2018 - 62,750 54,750 40,250 5,000 VA1 - mortgage loan - 31,615 31,699 31,782 31,864 CH1 - mortgage loan - - - - 25,000 Total Consolidated Debt $ 59,750 $ 154,365 $ 146,449 $ 132,032 $ 121,864 Weighted average interest rate 3.71% Floating rate vs. fixed rate debt 100% / 0% 59% / 41% 55% / 45% 51% / 49% 46% / 54% (1) See the most recent filed Form 10-K or 10-Q for information on specific debt instruments. (2) Each debt instrument's interest rate is based on LIBOR at December 31, 2012, plus applicable spread. (3) On January 3, 2013, the Company amended and restated its revolving credit facility, which among other things, extended the maturity date and increased the availability from $225.0 million to $355.0 million. The new credit facility is unsecured, compared to the prior facility which was secured by five assets.

Interest Summary and Debt Covenants Debt Covenants (1) Interest Expense Components Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix (in thousands) 20 Three Months Ended: December 31, September 30, June 30, March 31, December 31, 2012 2012 2012 2012 2011 Interest expense and fees $ 1,304 $ 1,433 $ 1,402 $ 1,253 $ 1,120 Amortization of deferred financing costs 374 435 436 436 371 Capitalized interest (364) (273) (529) (671) (653) Total interest expense $ 1,314 $ 1,595 $ 1,309 $ 1,018 $ 838 Revolving Credit Facility December 31, September 30, June 30, March 31, December 31, Required Compliance 2012 2012 2012 2012 2011 Fixed charge coverage ratio Greater than 1.75x 12.1x 18.3x 15.8x 14.9x 15.9x Total indebtedness to gross asset value Less than 60% 7.6% 12.7% 13.0% 13.1% 13.7% Secured debt to gross asset value Less than 40% 5.2% NA NA NA NA Unhedged variable rate debt to gross asset value Less than 30% 5.2% 4.9% 4.6% 3.7% 3.1% Facility availability $355,000 $202,500 $202,500 $202,500 $158,100 Borrowings outstanding - (62,750) (54,750) (40,250) (5,000) Outstanding letters of credit (8,540) (8,620) (8,620) (8,620) (8,600) Current availability $346,460 $131,130 $139,130 $153,630 $144,500 (1) On January 3, 2013, the Company amended and restated its revolving credit facility, which among other things, change the required financial covenants. The financial December 31, 2012 covenants above are in accordance with the Second Amended and Restated Agreement.

2013 Guidance Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix (in thousands, except per share amounts) 21 Projected per share and unit information: Low High Net income attributable to common shares $0.37 $0.47 Real Estate depreciation and amortization 1.35 FFO $1.72 $1.82 Projected operating results: Total operating revenues $ 237,000 $ 247,000 General and administrative expenses $ 28,000 $ 30,000 Adjusted EBITDA $ 105,000 $ 110,000 Significant guidance drivers: Rental churn rate per quarter 1% 2% Cash rent growth on data center renewals 4% 7% Development capital expenditures $ 200,000 $ 225,000 Recurring capital expenditures $ 4,000 $ 8,000 The annual guidance provided below represents forward-looking projections, which are based on

current economic conditions, internal assumptions about our existing customer base and the supply

and demand dynamics of the markets in which we operate. Further, the guidance does not include the

impact of any future financing, investment or disposition activities. Please refer to the press release

for additional information on forward-looking statements.

Appendix This document includes certain non-GAAP financial measures that management believes are helpful in understanding our business, as further described below. Our definition and calculation of non-GAAP financial measures may differ from those of other REITs, and therefore, may not be comparable. The non-GAAP measures should not be considered an alternative to net income as an indicator of our performance and should be considered only a supplement to net income, cash flows from operating, investing or financing activities as a measure of profitability and/or liquidity, computed in accordance with GAAP. Definitions Funds From Operations “FFO” – is a supplemental measure of our performance which should be considered along with, but not as an alternative to, net income and cash provided by operating activities as a measure of operating performance and liquidity. We calculate FFO in accordance with the standards established by the National Association of Real Estate Investment Trusts (“NAREIT”). FFO represents net income (loss) (computed in accordance with GAAP), excluding gains (or losses) from sales of property and impairment write-downs of depreciable real estate, plus real estate related depreciation and amortization (excluding amortization of deferred financing costs) and after adjustments for unconsolidated partnerships and joint ventures. Our management uses FFO as a supplemental performance measure because, in excluding real estate related depreciation and amortization and gains and losses from property dispositions, it provides a performance measure that, when compared year over year, captures trends in occupancy rates, rental rates and operating costs. We offer this measure because we recognize that FFO will be used by investors as a basis to compare our operating performance with that of other REITs. However, because FFO excludes depreciation and amortization and captures neither the changes in the value of our properties that result from use or market conditions, nor the level of capital expenditures and capitalized leasing commissions necessary to maintain the operating performance of our properties, all of which have real economic effect and could materially impact our financial condition and results from operations, the utility of FFO as a measure of our performance is limited. FFO is a non-GAAP measure and should not be considered a measure of liquidity, an alternative to net income, cash provided by operating activities or any other performance measure determined in accordance with GAAP, nor is it indicative of funds available to fund our cash needs, including our ability to pay dividends or make distributions. In addition, our calculations of FFO are not necessarily comparable to FFO as calculated by other REITs that do not use the same definition or implementation guidelines or interpret the standards differently from us. Investors in our securities should not rely on these measures as a substitute for any GAAP measure, including net income. Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 22

Appendix Adjusted Funds From Operations “AFFO” – is a non-GAAP measure that is used as a supplemental operating measure specifically for comparing year over year ability to fund dividend distribution from operating activities. AFFO is used by us as a basis to address our ability to fund our dividend payments. We calculate adjusted funds from operations by adding to or subtracting from FFO 1.: Plus: Amortization of deferred financing costs 2. Plus: Non-cash compensation 3. Plus: Non-real estate depreciation 4. Plus: Below market debt amortization 5. Less: Straight line rents adjustments 6. Less: Above and below market leases 7. Less: Maintenance capital investment 8. Less: Tenant improvement capital investment 9. Less: Capitalized leasing commissions AFFO is not intended to represent cash flow from operations for the period, and is only intended to provide an additional measure of performance by adjusting the effect of certain items noted above included in FFO. AFFO is a widely reported measure by other REITs, however, other REITs may use different methodologies for calculating AFFO and, accordingly, our AFFO may not be comparable to other REITs. Earnings before Interest, Taxes, Depreciation and Amortization (EBITDA) and Adjusted EBITDA - EBITDA is defined as earnings before interest, taxes, depreciation and amortization. We calculate adjusted EBITDA by adding our non-cash compensation expense, transaction costs and litigation settlement expense to EBITDA as well as adjusting for the impact of gains or losses on early extinguishment of debt. Management uses EBITDA and adjusted EBITDA as indicators of our ability to incur and service debt. In addition, we consider EBITDA and adjusted EBITDA to be appropriate supplemental measures of our performance because they eliminate depreciation and interest, which permits investors to view income from operations without the impact of non-cash depreciation or the cost of debt. However, because EBITDA and adjusted EBITDA are calculated before recurring cash charges including interest expense and taxes, and are not adjusted for capital expenditures or other recurring cash requirements of our business, their utilization as a cash flow measurement is limited. Overview Financial Statements Operating Portfolio Development and Capital Expenditures Capital Structure 2013 Guidance Appendix 23

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CoreSite Realty 8-KResults of Operations and Financial Condition