Earnings Release and Supplemental Information Quarter ended March 31, 2015 ®2015 CoreSite Realty Corporation, All Rights Reserved.

Overview Earnings Release 3 Company Profile 8 Summary of Financial Data 10 Financial Statements Consolidated Balance Sheets 11 Consolidated Statements of Operations 12 Reconciliations of Net Income to FFO, AFFO, EBITDA and Adjusted EBITDA 13 Operating Portfolio Operating Properties 14 Leasing Statistics 15 Geographic and Vertical Diversification 17 10 Largest Customers 18 Development Capital Expenditures and Completed Pre-Stabilized Projects 19 Development Summary 20 Capital Structure Market Capitalization and Debt Summary 21 Interest Summary and Debt Covenants 22 Components of Net Asset Value 23 2015 Guidance 24 Appendix 25 Table of Contents 2

Data center revenue increased 18% year over year DENVER, CO – APRIL 23, 2015 CoreSite Realty Corporation (NYSE:COR), a premier provider of secure, reliable, high-performance data center solutions across the US, today announced financial results for the first quarter ended March 31, 2015. Quarterly and Subsequent Highlights • Reported first-quarter funds from operations (“FFO”) of $0.64 per diluted share and unit, representing 25.5% growth year over year, excluding non-recurring items in Q1 2014 • Reported first-quarter total operating revenues of $74.8 million, representing a 17.3% increase year over year; total data center revenues increased 17.7% year over year • Executed 54,385 net rentable square feet of new and expansion turn-key data center leases representing $8.9 million of annualized GAAP rent at a rate of $163 per square foot • Commenced 60,797 net rentable square feet of new and expansion leases representing $9.2 million of annualized GAAP rent at a rate of $152 per square foot, increasing stabilized data center occupancy to 88.2% • Realized rent growth on signed renewals of 5.3% on a cash basis and 11.4% on a GAAP basis and recorded rental churn of 2.2% • Following the end of the first quarter, executed an agreement to construct a 136,580 square-foot powered shell on the Santa Clara campus 100% pre-leased to an existing strategic customer Tom Ray, CoreSite’s Chief Executive Officer, commented, “We had a solid first quarter, both in financial results and operational performance, reflecting continued execution of our business plan.” Mr. Ray continued, “We believe that CoreSite remains well positioned within our industry and that the supply and demand dynamics in the markets we serve remain favorable. 2015 is off to a solid start and we remain optimistic about the internal growth opportunities inherent in our data center portfolio.” Financial Results CoreSite reported FFO attributable to shares and units of $30.2 million for the three months ended March 31, 2015, a 26.9% increase year over year, excluding non-recurring items in the first quarter of 2014, and an increase of 4.2% on a sequential-quarter basis. FFO per diluted share and unit increased 25.5% to $0.64 for the three months ended March 31, 2015, as compared to $0.51 per diluted share and unit for the three months ended March 31, 2014, excluding non-recurring items. On a sequential-quarter basis, FFO per diluted share increased 4.9%. CORESITE REPORTS FIRST-QUARTER REVENUE AND FFO PER SHARE GROWTH, EXCLUDING NON-RECURRING ITEMS IN THE YEAR-AGO PERIOD, OF 17% AND 26%, RESPECTIVELY 3 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE COMPONENTS OF NAV 2015 GUIDANCE APPENDIX

Total operating revenues for the three months ended March 31, 2015, were $74.8 million, a 17.3% increase year over year and an increase of 3.1% on a sequential-quarter basis. Total data center revenues for the three months ended March 31, 2015, were $72.6 million, a 17.7% increase year over year and an increase of 2.8% on a sequential-quarter basis. CoreSite reported net income attributable to common shares of $4.6 million, or $0.21 per diluted share. Sales Activity CoreSite executed 100 new and expansion turn-key data center leases representing $8.9 million of annualized GAAP rent during the first quarter, comprised of 54,385 NRSF at a weighted-average GAAP rental rate of $163 per NRSF. CoreSite’s first-quarter data center lease commencements totaled 60,797 NRSF at a weighted average GAAP rental rate of $152 per NRSF, which represents $9.2 million of annualized GAAP rent. CoreSite’s renewal leases signed in the first quarter totaled $7.2 million in annualized GAAP rent, comprised of 40,446 NRSF at a weighted-average GAAP rental rate of $179 per NRSF, reflecting a 5.3% increase in rent on a cash basis and an 11.4% increase on a GAAP basis. The first-quarter rental churn rate was 2.2%. Development Activity Santa Clara – In April 2015, CoreSite began construction on a 136,580 square-foot powered shell data center on land CoreSite owns on its Santa Clara campus. The building, which will be known as SV6, is 100% pre-leased. As of March 31, 2015, CoreSite has incurred $1.2 million of the estimated $27.0 million required to complete the development project, and expects to deliver the build-to-suit to a strategic customer in the first half of 2016. Virginia – During the first quarter, CoreSite placed into service 44,036 NRSF associated with Phase 1 at VA2 and the lease for 100% of the space commenced on April 1, 2015. As of March 31, 2015, CoreSite had 48,137 NRSF of data center space under construction at Phase 2 at VA2 and had incurred $7.4 million of the estimated $13.3 million required to complete Phase 2. CoreSite expects to complete construction in the second quarter of 2015. New York – During the first quarter, CoreSite had 49,050 NRSF under construction at Phase 2 at NY2, which is expected to be completed in the second quarter of 2015. As of March 31, 2015, CoreSite had incurred $7.9 million of the estimated $21.3 million required to complete this project. Additional markets – CoreSite had 26,853 NRSF of turn-key data center capacity under construction as of March 31, 2015, across the Company’s existing facilities at BO1 (Boston) and CH1 (Chicago). As of the end of the first quarter, CoreSite had incurred $3.2 million of the estimated $16.5 million required to complete these projects. Quarter Ended March 31, 2015 4 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE COMPONENTS OF NAV 2015 GUIDANCE APPENDIX

Balance Sheet and Liquidity As of March 31, 2015, CoreSite had $333.8 million of total long-term debt outstanding, correlating to 2.2 times first-quarter annualized adjusted EBITDA, and $448.8 million of long-term debt and preferred stock, correlating to 3.0 times first-quarter annualized adjusted EBITDA. At quarter end, CoreSite had $12.1 million of cash available on its balance sheet and $163.9 million of capacity available under its revolving credit facility. Dividend On March 12, 2015, CoreSite announced a dividend of $0.42 per share of common stock and common stock equivalents for the first quarter of 2015. The dividend was paid on April 15, 2015, to shareholders of record on March 31, 2015. CoreSite also announced on March 12, 2015, a dividend of $0.4531 per share of Series A preferred stock for the period January 15, 2015, to April 14, 2015. The preferred dividend was paid on April 15, 2015, to shareholders of record on March 31, 2015. 2015 Guidance CoreSite is maintaining its 2015 guidance of FFO per diluted share and unit in the range of $2.55 to $2.65. In addition, CoreSite is maintaining its 2015 guidance for net income attributable to common shares in the range of $0.75 to $0.85 per diluted share, with the difference between FFO and net income being real estate depreciation and amortization. CoreSite is increasing its guidance for 2015 total capital expenditures by $30 million to a range of $115 million to $145 million to primarily reflect the development of the powered shell build-to-suit data center on its Santa Clara campus. This outlook is predicated on current economic conditions, internal assumptions about CoreSite’s customer base, and the supply and demand dynamics of the markets in which CoreSite operates. The guidance does not include the impact of any future financing, investment or disposition activities beyond what has already been disclosed. Upcoming Conferences and Events CoreSite will participate in NAREIT’s REITWeek conference from June 9, 2015, through June 10, 2015, at the New York Hilton in New York, NY. Quarter Ended March 31, 2015 5 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE COMPONENTS OF NAV 2015 GUIDANCE APPENDIX

Conference Call Details CoreSite will host a conference call on April 23, 2015, at 12:00 p.m., Eastern Time (10:00 a.m., Mountain Time), to discuss its financial results, current business trends and market conditions. The call can be accessed live over the phone by dialing 877-407-3982 for domestic callers or 201-493-6780 for international callers. A replay will be available shortly after the call and can be accessed by dialing 877-870-5176 for domestic callers or 858-384-5517 for international callers. The passcode for the replay is 13604923. The replay will be available until April 30, 2015. Interested parties may also listen to a simultaneous webcast of the conference call by logging on to CoreSite’s website at www.CoreSite.com and clicking on the “Investors” link. The on-line replay will be available for a limited time beginning immediately following the call. About CoreSite CoreSite Realty Corporation (NYSE:COR) delivers secure, reliable, high-performance data center solutions across eight key North American markets. More than 800 of the world’s leading enterprises, network operators, cloud providers, and supporting service providers choose CoreSite to connect, protect and optimize their performance-sensitive data, applications and computing workloads. Our scalable, flexible solutions and 350+ dedicated employees consistently deliver unmatched data center options – all of which leads to a best-in-class customer experience and lasting relationships. For more information, visit www.CoreSite.com. CoreSite Investor Relations Contact Greer Aviv CoreSite Investor Relations Director +1 303.405.1012 +1 303.222.7276 Greer.Aviv@CoreSite.com Quarter Ended March 31, 2015 6 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE COMPONENTS OF NAV 2015 GUIDANCE APPENDIX

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. Quarter Ended March 31, 2015 7 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Company Profile CoreSite delivers secure, reliable, high-performance data center solutions across eight key North American markets. NY2 SILICON VALLEY SV1 SV3 SV5 SV2 SV4 SV6 LOS ANGELES LA1 LA2 DENVER HQ DE1 DE2 CHICAGO CH1 N VIRGINIA/DC VA1 DC1 VA2 BOSTON BO1 MIAMI MI1 NEW YORK NY1 NY2 8 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Company Profile Secure, Reliable and Compliant Six 9s uptime for four consecutive years Physical security standards enable regulatory compliance requirements Payment Card Industry certification Rigorous internal security training Operational excellence in security and environmental controls Scalable Newest data centers, NY2 and VA2, located in Secaucus, NJ, and Reston, VA 17 operating data centers in eight of the US’ largest commercial and data center markets 2.5+ million gross square feet Ability to nearly occupied data center footprint on land and buildings currently owned High-Performance Cloud-enabled, network-rich data center campuses Over 275 network service providers supported by robust IX services to key public clouds 15,000+ cross-connects Enabling enterprise with support ecosystems Best-in-Class Customer Experience 350+ professionals with dedicated industry expertise Experienced and committed operations and facility personnel Dedicated implementation resources to ensure a seamless onboarding process 24/7 customer support and remote hands 9 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX VA2

Summary of Financial Data (in thousands, except per share and NRSF data) Three Months Ended Summary of Results March 31, 2015 December 31, 2014 March 31, 2014 Operating revenues $ 74,757 $ 72,492 $ 63,731 Data center revenues 72,623 70,632 61,716 Net income 12,060 12,306 8,118 Net income attributable to common shares 4,568 4,664 2,733 Funds from operations (FFO) to shares and units 30,193 28,981 22,870 Adjusted funds from operations (AFFO) 25,154 23,143 19,356 EBITDA 36,188 36,107 27,191 Adjusted EBITDA 37,951 36,258 30,059 Per share - diluted: Net income attributable to common shares $ 0.21 $ 0.21 $ 0.13 FFO per common share and OP unit $ 0.64 $ 0.61 $ 0.49 As of March 31, 2015 December 31, 2014 September 30, 2014 June 30, 2014 March 31, 2014 Dividend Activity Dividends declared per share and OP unit $ 0.42 $ 0.42 $ 0.35 $ 0.35 $ 0.35 AFFO payout ratio 79.1% 85.4% 86.2% 76.2% 84.4% Operating Portfolio Statistics Operating data center properties 17 17 16 16 16 Stabilized operating data center NRSF 1,354,235 1,323,210 1,334,914 1,326,332 1,326,332 Stabilized data center NRSF occupied 1,194,994 1,156,486 1,153,345 1,132,894 1,101,305 Stabilized data center % occupied 88.2% 87.4% 86.4% 85.4% 83.0% Turn-Key Data Center Same Store Statistics MRR per Cabinet Equivalent $ 1,408 $ 1,413 $ 1,390 $ 1,364 $ 1,340 Data center NRSF % occupied 83.1% 80.2% 78.4% 76.4% 71.6% Market Capitalization, Debt & Preferred Stock Total enterprise value $ 2,755,403 $ 2,273,458 $ 1,967,868 $ 1,945,279 $ 1,831,690 Total debt outstanding 333,750 318,500 305,250 276,750 260,000 Total debt and preferred stock outstanding 448,750 433,500 420,250 391,750 375,000 Debt to: Annualized Adjusted EBITDA 2.2x 2.2x 2.3x 2.0x 2.2x Undepreciated book value of total assets 25.3% 24.7% 24.2% 22.3% 21.6% Debt & Preferred Stock to: Annualized Adjusted EBITDA 3.0x 3.0x 3.2x 2.9x 3.1x Undepreciated book value of total assets 34.0% 33.6% 33.3% 31.5% 31.1% 10 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Consolidated Balance Sheets (in thousands) March 31, 2015 December 31, 2014 Assets: Investments in real estate: Land $ 80,398 $ 78,983 Buildings and improvements 928,562 888,966 1,008,960 967,949 Less: Accumulated depreciation and amortization (231,987) (215,978) Net investment in operating properties 776,973 751,971 Construction in progress 165,154 178,599 Net investments in real estate 942,127 930,570 Cash and cash equivalents 12,058 10,662 Accounts and other receivables, net 10,715 10,290 Lease intangibles, net 6,424 7,112 Goodwill 41,191 41,191 Other assets 73,772 75,600 Total assets $ 1,086,287 $ 1,075,425 Liabilities and equity: Liabilities Revolving credit facility $ 233,750 $ 218,500 Senior unsecured term loan 100,000 100,000 Accounts payable and accrued expenses 44,666 42,463 Accrued dividends and distributions 22,374 22,355 Deferred rent payable 8,751 8,985 Acquired below-market lease contracts, net 5,349 5,576 Unearned revenue, prepaid rent and other liabilities 21,800 19,205 Total liabilities 436,690 417,084 Stockholders' equity Series A cumulative preferred stock 115,000 115,000 Common stock, par value $0.01 214 212 Additional paid-in capital 277,181 275,038 Accumulated other comprehensive loss (574) (125) Distributions in excess of net income (72,202) (67,538) Total stockholders' equity 319,619 322,587 Noncontrolling interests 329,978 335,754 Total equity 649,597 658,341 Total liabilities and equity $ 1,086,287 $ 1,075,425 11 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Consolidated Statements of Operations (in thousands, except share and per share data) 12 Three Months Ended March 31, 2015 December 31, 2014 March 31, 2014 Operating revenues: Data center revenue: Rental revenue $ 41,323 $ 39,142 $ 34,899 Power revenue 19,669 19,963 16,002 Interconnection revenue 10,215 9,536 8,059 Tenant reimbursement and other 1,416 1,991 2,756 Total data center revenue 72,623 70,632 61,716 Office, light-industrial and other revenue 2,134 1,860 2,015 Total operating revenues 74,757 72,492 63,731 Operating expenses: Property operating and maintenance 19,780 20,253 16,289 Real estate taxes and insurance 1,935 2,519 2,966 Depreciation and amortization 22,816 22,422 17,882 Sales and marketing 3,782 3,413 3,588 General and administrative 7,865 6,260 7,705 Rent 5,243 5,148 5,066 Impairment of internal-use software - - 922 Transaction costs - - 4 Total operating expenses 61,421 60,015 54,422 Operating income 13,336 12,477 9,309 Gain on real estate disposal 36 1,208 - Interest income 2 1 2 Interest expense (1,265) (1,362) (1,173) Income before income taxes 12,109 12,324 8,138 Income tax expense (49) (18) (20) Net income 12,060 12,306 8,118 Net income attributable to noncontrolling interests 5,408 5,557 3,301 Net income attributable to CoreSite Realty Corporation 6,652 6,749 4,817 Preferred stock dividends (2,084) (2,085) (2,084) Net income attributable to common shares $ 4,568 $ 4,664 $ 2,733 Net income per share attributable to common shares: Basic $ 0.21 $ 0.22 $ 0.13 Diluted $ 0.21 $ 0.21 $ 0.13 Weighted average common shares outstanding: Basic 21,372,157 21,303,795 20,992,758 Diluted 21,978,307 21,794,138 21,521,838 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Reconciliations of Net Income to FFO, AFFO, EBITDA and Adjusted EBITDA (in thousands, except per share data) Reconciliation of Net Income to FFO Reconciliation of FFO to AFFO Reconciliation of Net Income to EBITDA and Adjusted EBITDA Three Months Ended March 31, 2015 December 31, 2014 March 31, 2014 Net income $ 12,060 $ 12,306 $ 8,118 Real estate depreciation and amortization 20,253 19,968 16,836 Gain on real estate disposal (36) (1,208) - FFO $ 32,277 $ 31,066 $ 24,954 Preferred stock dividends (2,084) (2,085) (2,084) FFO available to common shareholders and OP unit holders $ 30,193 $ 28,981 $ 22,870 Weighted average common shares outstanding - diluted 21,978 21,794 21,522 Weighted average OP units outstanding - diluted 25,361 25,361 25,361 Total weighted average shares and units outstanding - diluted 47,339 47,155 46,883 FFO per common share and OP unit - diluted $ 0.64 $ 0.61 $ 0.49 Three Months Ended March 31, 2015 December 31, 2014 March 31, 2014 FFO available to common shareholders and unit holders $ 30,193 $ 28,981 $ 22,870 Adjustments: Amortization of deferred financing costs 294 420 580 Non-cash compensation 1,569 1,359 1,716 Non-real estate depreciation 2,563 2,454 1,046 Straight-line rent adjustment (1,064) (1,390) (436) Amortization of above and below market leases (128) (118) (70) Impairment of internal-use software - - 922 Recurring capital expenditures (1,981) (254) (1,673) Tenant improvements (2,197) (1,059) (1,208) Capitalized leasing costs (4,095) (7,250) (4,391) AFFO available to common shareholders and OP unit holders $ 25,154 $ 23,143 $ 19,356 Three Months Ended March 31, 2015 December 31, 2014 March 31, 2014 Net income $ 12,060 $ 12,306 $ 8,118 Adjustments: Interest expense, net of interest income 1,263 1,361 1,171 Income tax expense 49 18 20 Depreciation and amortization 22,816 22,422 17,882 EBITDA $ 36,188 $ 36,107 $ 27,191 Non-cash compensation 1,569 1,359 1,716 Gain on real estate disposal (36) (1,208) - Transaction costs / litigation 230 - 230 Impairment of internal-use software - - 922 Adjusted EBITDA $ 37,951 $ 36,258 $ 30,059 13 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Operating Properties Data Center Operating NRSF Stabilized Pre-Stabilized Total NRSF Under Construction Held for Development NRSF Market/Facilities Annualized Rent ($000)(1) Total Percent Occupied(2) Total(3) Percent Occupied Total Percent Occupied(2) Total NRSF Los Angeles One Wilshire Campus LA1* $ 25,304 139,053 82.8 % - - % 139,053 82.8 % - - 139,053 LA2 18,887 191,202 87.0 33,711 4.2 224,913 74.6 - 199,978 424,891 Los Angeles Total 44,191 330,255 85.3 33,711 4.2 363,966 77.7 - 199,978 563,944 San Francisco Bay SV1 6,814 84,045 83.5 - - 84,045 83.5 - - 84,045 SV2 8,189 76,676 87.2 - - 76,676 87.2 - - 76,676 Santa Clara Campus 26,822 237,316 91.6 14,857 74.4 252,173 90.5 136,580 166,000 554,753 San Francisco Bay Total 41,825 398,037 89.0 14,857 74.4 412,894 88.5 136,580 166,000 715,474 Northern Virginia VA1 25,583 201,719 87.6 - - 201,719 87.6 - - 201,719 VA2 - - - 44,036 - 44,036 - 48,137 96,274 188,447 DC1* 3,085 22,137 89.3 - - 22,137 89.3 - - 22,137 Northern Virginia Total 28,668 223,856 87.7 44,036 - 267,892 73.3 48,137 96,274 412,303 Boston BO1 14,269 166,026 99.4 - - 166,026 99.4 15,149 72,501 253,676 Chicago CH1 13,188 146,463 88.2 20,240 28.1 166,703 80.9 11,704 - 178,407 New York NY1* 5,858 48,404 73.4 - - 48,404 73.4 - - 48,404 NY2 3,172 - - 52,692 66.7 52,692 66.7 49,050 134,508 236,250 New York Total 9,030 48,404 73.4 52,692 66.7 101,096 69.9 49,050 134,508 284,654 Miami MI1 1,817 30,176 80.9 - - 30,176 80.9 - 13,154 43,330 Denver DE1* 1,053 5,878 90.1 - - 5,878 90.1 - - 5,878 DE2* 329 5,140 64.2 - - 5,140 64.2 - - 5,140 Denver Total 1,382 11,018 78.0 - - 11,018 78.0 - - 11,018 Total Data Center Facilities $ 154,370 1,354,235 88.2 % 165,536 32.2 % 1,519,771 82.1 % 260,620 682,415 2,462,806 Office & Light-Industrial 7,014 358,648 74.9 - - 358,648 74.9 - - 358,648 Total Portfolio $ 161,384 1,712,883 85.5 % 165,536 32.2 % 1,878,419 80.8 % 260,620 682,415 2,821,454 * Indicates properties in which we hold a leasehold interest. (1) On a gross basis, our total portfolio annualized rent was approximately $165.6 million as of March 31, 2015, which reflects the addition of $4.2 million in operating expense reimbursements to contractual net rent under modified gross and triple-net leases. (2) Includes customer leases that have commenced and are occupied as of March 31, 2015. If all leases signed during the current and prior periods had commenced, the percent occupied would have been as follows: Percent Leased Stabilized Pre-Stabilized Total Total Data Center Facilities 90.6% 59.3% 87.2% Total Portfolio 87.5% 59.3% 85.0% (3) VA2 Phase 1, which consists of 44,036 NRSF and classified as pre-stabilized data center, is 100% leased to a single customer as of March 31, 2015. The customer lease commenced on April 1, 2015. 14 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX See Appendix for definitions.

Leasing Statistics Data Center Leasing Activity MRR per Cabinet Equivalent (Turn-key Data Center Same Store)(1) GAAP GAAP Leasing Number Annualized Total Annualized Rental Cash GAAP Activity of Rent Leased Rent per Churn Rent Rent Period Leases(1) (000's) NRSF Leased NRSF Rate Growth Growth New/expansion leases commenced Q1 2015 110 9,224 60,797 152 Q4 2014 106 4,943 34,009 145 Q3 2014 115 6,066 45,014 135 Q2 2014 126 8,152 60,587 135 Q1 2014 119 3,763 28,125 134 New/expansion leases signed Q1 2015 100 8,861 54,385 163 Q4 2014 96 11,075 91,662 121 (2) Q3 2014 118 7,607 54,123 141 Q2 2014 121 9,368 58,909 159 Q1 2014 131 5,139 39,783 129 Renewal leases signed Q1 2015 122 7,222 40,446 179 2.2% 5.3% 11.4% Q4 2014 78 6,705 43,863 153 1.4% 2.6% 5.2% Q3 2014 123 12,078 55,262 219 1.2% 3.0% 10.6% Q2 2014 77 7,009 41,890 167 1.8% 2.1% 8.1% Q1 2014 74 3,535 22,291 159 1.2% 4.7% 9.4% (1) Number of leases represents each agreement with a customer; a lease agreement could include multiple spaces and a customer could have multiple leases. (2) During Q4 2014, we signed a 44,036 NRSF lease with a single customer for the entire VA2 Phase 1 facility. 15 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX 7% y-o-y 7% y-o-y 8% y-o-y 7% y-o-y 7% y-o-y 6.8% y-o-y 7.2% y-o-y 7.7% y-o-y 7.0% y-o-y 7.1% y-o-y $1,340 $1,364 $1,390 $1,413 $1,408 $1,300 $1,350 $1,400 $1,450 Q1'14 Q2'14 Q3'14 Q4'14 Q1'15 3 .6% y - o - y 6.2% y - o - y 5.4% y - o - y 5.2% y - o - y 5 .1% y - o - y

Leasing Statistics Lease Expirations (total portfolio, including total data center and office and light-industrial “OLI”) Lease Distribution (total portfolio, including total data center and office and light-industrial “OLI”) Total Percentage Percentage Number Percentage Operating of Total Annualized of Total of of All NRSF of Operating Rent Annualized NRSF Under Lease Leases Leases Leases NRSF ($000) Rent Unoccupied data center - - % 271,469 14.5 % $ - - % Unoccupied OLI - - 89,875 4.8 - - Data center NRSF: 5,000 or less 1,496 90.6 504,341 26.8 85,904 53.3 5,001 - 10,000 26 1.6 178,917 9.5 23,001 14.3 10,001 - 25,000 16 1.0 205,819 11.0 27,188 16.8 Greater than 25,000 2 0.1 63,545 3.4 7,946 4.9 Powered shell 13 0.8 295,680 15.7 10,331 6.4 OLI 97 5.9 268,773 14.3 7,014 4.3 Portfolio Total 1,650 100.0 % 1,878,419 100.0 % $ 161,384 100.0 % Total Annualized Number Operating Percentage Percentage Annualized Annualized Rent Per of NRSF of of Total Annualized of Total Rent Per Rent at Leased Leases Expiring Operating Rent Annualized Leased Expiration NRSF at Year of Lease Expiration Expiring(1) Leases NRSF ($000) Rent NRSF ($000)(2) Expiration Unoccupied data center - 271,469 14.5 % $ - - % $ - $ - $ - Unoccupied OLI - 89,875 4.8 - - - - - 2015 490 201,372 10.7 30,692 19.0 152 30,749 153 2016 452 236,481 12.6 34,334 21.3 145 35,905 152 2017 353 204,592 10.9 35,225 21.8 172 37,532 184 2018 133 205,140 10.9 24,892 15.4 121 28,613 139 2019 72 163,614 8.7 12,512 7.8 76 18,745 115 2020-Thereafter 53 237,103 12.6 16,715 10.4 71 20,350 86 OLI (3) 97 268,773 14.3 7,014 4.3 26 6,999 26 Portfolio Total / Weighted Average 1,650 1,878,419 100.0 % $ 161,384 100.0 % $ 106 $ 178,893 $ 118 (1) Includes leases that upon expiration will automatically be renewed, primarily on a year-to-year 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 final monthly contractual rent under existing customer leases as of March 31, 2015, 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) The office and light-industrial leases are scheduled to expire as follows: NRSF of Annualized Expiring Rent Year Leases ($000) 2015 38,191 $ 677 2016 61,330 1,466 2017 9,073 250 2018 5,046 137 2019 4,948 149 2020-Thereafter 150,185 4,335 Total OLI 268,773 $ 7,014  16 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Geographic and Vertical Diversification Geographic Diversification Vertical Diversification Percentage of Total Data Metropolitan Market Center Annualized Rent Los Angeles 28.6 % San Francisco Bay 27.1 Northern Virginia 18.6 Boston 9.3 Chicago 8.5 New York 5.8 Miami 1.2 Denver 0.9 Total 100.0 % Percentage of Total Data Vertical Center Annualized Rent Enterprise: Digital Content & Multimedia 25.9 % SI & MSP 13.2 Other Enterprise 12.3 Total Enterprise 51.4 Networks & Mobility 25.4 Cloud 23.2 Total 100.0 % 17 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX Los Angeles 28.6% San Francisco Bay 27.1% Northern Virginia 18.6% Boston 9.3% Chicago 8.5% New York 5.8% Miami 1.2% Denver 0.9% Digital Content & Multimedia 25.9% SI & MSP 13.2% Other Enterprise 12.3% Networks & Mobility 25.4% Cloud 23.2%

10 Largest Customers 10 Largest Customers (total portfolio, including data center and office and light-industrial) Weighted Percentage Percentage Average Number Total of Total Annualized of Total Remaining of Occupied Operating Rent Annualized Lease Term in Customer Industry CoreSite Vertical Locations NRSF NRSF(1) ($000) Rent(2) Months(3) 1 Technology Cloud 8 142,671 7.6 % $ 10,099 6.3 % 52 2 Technology Enterprise - SI & MSP 3 68,746 3.7 8,153 5.0 33 3 Technology Enterprise - Digital Content 10 66,256 3.5 5,972 3.7 8 4 Technology Enterprise - Digital Content 4 17,841 1.0 5,808 3.6 18 5 Technology Cloud 1 28,923 1.5 4,118 2.5 43 6 Government* Enterprise - Other 1 130,960 7.0 3,906 2.4 81 7 Technology Enterprise - Digital Content 2 15,113 0.8 3,719 2.3 36 8 Financial(4) Enterprise - Other 2 12,188 0.6 3,230 2.0 113 9 Technology Enterprise - SI & MSP 1 6,417 0.3 3,025 1.9 22 10 Technology Network 12 12,321 0.7 2,638 1.7 35 Total/Weighted Average 501,436 26.7 % $ 50,668 31.4 % 41 * Denotes customer using space for general office purposes. (1) Represents the customer’s total occupied square feet divided by the total operating NRSF in the portfolio which, as of March 31, 2015, consisted of 1,878,419 NRSF. (2) Represents the customer’s total annualized rent divided by the total annualized rent in the portfolio as of March 31, 2015, which was approximately $161.4 million. (3) Weighted average based on percentage of total annualized rent expiring calculated as of March 31, 2015. (4) Customer's lease term includes auto renewal provisions at the end of years four and six, which the customer may opt out of by paying termination fees of $0.4 million and $0.3 million, respectively. 18 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Capital Expenditures and Completed Pre-Stabilized Projects (in thousands, except NRSF data) Completed Pre-Stabilized Projects Capital Expenditures and Repairs and Maintenance  Three Months Ended March 31, 2015 December 31, 2014 September 30, 2014 June 30, 2014 March 31, 2014 Data center expansion(1) $ 21,078 $ 19,147 $ 14,166 $ 32,082 $ 18,917 Non-recurring investments(2) 3,872 1,838 2,304 2,671 5,714 Tenant improvements 2,197 1,059 666 1,579 1,208 Recurring capital expenditures(3) 1,981 254 1,125 1,377 1,673 Total capital expenditures $ 29,128 $ 22,298 $ 18,261 $ 37,709 $ 27,512 Repairs and maintenance expense(4) $ 2,349 $ 2,485 $ 2,186 $ 2,600 $ 2,284 (1) Data center expansion capital expenditures include new data center construction, development projects adding capacity to existing data centers and other revenue generating investments. (2) Non-recurring investments include upgrades to existing data center or office space and company-wide improvements that are ancillary to revenue generation such as internal system development and system-wide security upgrades, which have a future economic benefit. (3) Recurring capital expenditures include required equipment upgrades within our operating portfolio, which have a future economic benefit. (4) Repairs and maintenance expense is classified within property operating and maintenance expense in the consolidated statement of operations. These expenditures represent recurring maintenance contracts and repairs to operating equipment necessary to maintain current operations. Projects/Facilities Metropolitan Area Completion NRSF Cost Percent Leased(1) Percent Occupied SV4 San Francisco Bay Apr 2013 14,857 $ 12,911 74.4 % 74.4 % CH1 Chicago Apr 2013 20,240 5,200 28.1 28.1 NY2 New York Dec 2013 18,103 14,417 78.2 75.1 LA2 Los Angeles Feb 2014 33,711 9,800 4.2 4.2 NY2 New York Mar 2014 16,484 14,540 73.4 73.4 NY2 New York Mar 2014 18,105 14,540 53.4 52.3 VA2 Northern Virginia Mar 2015 44,036 32,298 100.0 - Total completed pre-stabilized 165,536 $ 103,706 59.3 % 32.2 % (1) Includes customer leases that have been signed as of March 31, 2015, but have not commenced. The percent leased is determined based on leased square feet as a proportion of total pre-stabilized NRSF. VA2 Phase 1 is 100% leased to a single customer as of December 31, 2014. The customer lease commenced April 1, 2015. 19 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Development Summary (in thousands, except NRSF data) Data Center Projects Under Construction Costs Projects/Facilities Metropolitan Area Estimated Completion NRSF Incurred to-date Estimated Total VA2 Phase 2 Northern Virginia Q2 2015 48,137 $ 7,351 $ 13,300 NY2 Phase 2 New York Q2 2015 49,050 7,910 21,330 CH1 Chicago Q3 2015 11,704 2,973 7,000 BO1 Boston Q1 2016 15,149 203 9,500 SV6(1) San Francisco Bay Q1 - Q2 2016 136,580 1,180 27,000 Total under construction 260,620 $ 19,617 $ 78,130 (1) Represents 136,580 NRSF of pre-sold dedicated build-to-suit space that was 100% leased in April 2015 and has an expected lease commencement date in the first half of 2016. Projects/Facilities Metropolitan Area Estimated NRSF Estimated Sellable Power (Megawatts) Estimated Incremental Costs Estimated Incremental Cost per MW New construction Santa Clara Campus(2) San Francisco Bay 200,000 12.0 - 18.0 Secaucus, NJ New York 47,211 - 147,211 3.0 - 9.0 Incremental capacity in existing facilities VA2 (Phases 3-4) Northern Virginia 96,274 6.0 $ 35,000 $ 5,833 NY2 (Phases 3-4) New York 75,769 8.5 57,000 6,706 BO1 Boston 72,501 6.0 50,000 8,333 LA2 Los Angeles 199,978 14.0 75,000 5,357 MI1 Miami 13,154 1.0 7,500 7,500 Total incremental capacity 457,676 35.5 $ 224,500 $ 6,324 Total new construction & incremental capacity 716,415 - 816,415 50.5 - 62.5 (1) Represents data center space that may be constructed on entitled and unentitled land and incremental data center capacity that may be constructed in existing facilities. The data presented represents management's best estimate of incremental costs that may vary based on estimated NRSF and power and are subject to market conditions and build-out specifications. (2) Includes 34,000 NRSF that is currently operating and classified as office and light-industrial space with the Operating Property table. 20 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX Held for Development(1)

Market Capitalization and Debt Summary (in thousands, except per share data) Market Capitalization Debt Maturities Debt Summary (1) Shares or Equivalents Outstanding Market Price / Liquidation Value as of March 31, 2015 Market Value Equivalents Common shares 22,023 $48.68 $ 1,072,080 Operating partnership units 25,361 $48.68 1,234,573 Liquidation value of preferred stock 4,600 $25.00 115,000 Total equity 2,421,653 Total debt 333,750 Total enterprise value $ 2,755,403 Total debt to annualized adjusted EBITDA 2.2x Total debt and preferred stock to annualized adjusted EBITDA 3.0x Maturity Outstanding as of: Maturity Date with March 31, December 31, Instrument Rate Date Extension 2015 2014 Revolving credit facility (2) 2.18% 1/3/2017 1/3/2018 $ 233,750 $ 218,500 Senior unsecured term loan (3) 3.23% 1/31/2019 1/31/2019 100,000 100,000 Total Debt $ 333,750 $ 318,500 Weighted average debt rate 2.49% Preferred Stock 7.25% N/A N/A 115,000 115,000 Total Debt and Preferred Stock $ 448,750 $ 433,500 Floating rate vs. fixed rate debt 70% / 30% 67% / 33% Floating rate vs. fixed rate debt and preferred stock 52% / 48% 50% / 50% (1) See the most recently filed Form 10-K and 10-Q for information on specific debt instruments. (2) The revolving credit facility interest rate is based on LIBOR at March 31, 2015, plus applicable spread. (3) Represents the effective interest rate as a result of the interest rate swap agreement associated with $100 million in 1-month LIBOR variable rate debt. 21 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Interest Summary and Debt Covenants (in thousands) Interest Expense Components Debt Covenants Three Months Ended March 31, 2015 December 31, 2014 March 31, 2014 Interest expense and fees $ 2,226 $ 2,183 $ 1,762 Amortization of deferred financing costs 294 420 580 Capitalized interest (1,255) (1,241) (1,169) Total interest expense $ 1,265 $ 1,362 $ 1,173 Percent capitalized 49.8% 47.7% 49.9% Revolving Credit Facility and Senior Unsecured Term Loan Required Compliance March 31, 2015 December 31, 2014 September 30, 2014 June 30, 2014 March 31, 2014 Fixed charge coverage ratio Greater than 1.75x 8.8x 8.4x 7.7x 7.5x 7.8x Total indebtedness to gross asset value Less than 60% 17.1% 17.2% 17.5% 16.4% 15.6% Secured debt to gross asset value Less than 40% 0.0% 0.0% 0.0% 0.0% 0.0% Unhedged variable rate debt to gross asset value Less than 30% 11.8% 11.6% 11.5% 10.2% 9.3% Facility availability $405,000 $405,000 $405,000 $405,000 $405,000 Borrowings outstanding (233,750) (218,500) (205,250) (176,750) (160,000) Outstanding letters of credit (7,330) (7,330) (7,330) (7,330) (8,390) Current availability $163,920 $179,170 $192,420 $220,920 $236,610 22 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Components of Net Asset Value (NAV) (in thousands) Reconciliation of Net Operating Income (NOI) Q1 2015 Annualized Operating Income $ 13,336 $ 53,344 Adjustments: Depreciation and amortization 22,816 91,264 General and administrative 7,865 31,460 Transaction costs / litigation 230 920 Net Operating Income $ 44,247 $ 176,988 Cash Net Operating Income (Cash NOI) Net Operating Income $ 44,247 $ 176,988 Adjustments: Straight-line rent (1,064) (4,256) Amortization of above and below-market leases (128) (512) Cash NOI $ 43,055 $ 172,220 Cash NOI with backlog (85.0% leased)(1) $ 45,890 $ 183,560 Cash stabilized NOI (93% leased) $ 50,209 $ 200,836 Data Center Projects Under Construction Construction in progress(2) $ 19,617 Remaining spend(2) 58,513 Total $ 78,130 Targeted annual yields 12% - 16% Annualized pro forma NOI range $9,400 - $12,500 Other Assets Remaining construction in progress(3) $ 145,537 Cash and cash equivalents 12,058 Accounts and other receivables 10,715 Other tangible assets 21,381 Total other assets $ 189,691 Liabilities Debt $ 333,750 Accounts payable, accrued and other liabilities 88,840 Preferred equity 115,000 Total liabilities $ 537,590 Weighted average common shares and units - diluted 47,339 (1) Cash NOI with backlog is adjusted to include one quarter of the cash backlog as of March 31, 2015, less any leasing of currently occupied NRSF and data center projects under development. (2) Does not include spend associated with leasing commissions. See page 20 for further breakdown of data center projects under construction. (3) Represents the book value of in progress capital projects, including land and shell building, of future NY2 and VA2 phases and other data center expansion, non-recurring investments, tenant improvements and recurring capital expenditures. 23 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX Cash Net Operating Income Development Projects Other Assets and Liabilities

2015 Guidance (in thousands, except per share amounts) 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. Projected per share and OP unit information: 2015 Implied Low High Mid 2014 Growth(1) Net income attributable to common shares $ 0.75 $ 0.85 $ 0.80 $ 0.66 21% Real estate depreciation and amortization 1.80 1.80 1.58 Gain on land disposal - - (0.02) FFO $ 2.55 $ 2.65 $ 2.60 $ 2.22 Non-recurring items: Q2 benefit from real estate tax accrual true-up - - - (0.08) Q1 and Q2 charges for software impairment - - - 0.04 FFO - excluding non-recurring items(2) $ 2.55 $ 2.65 $ 2.60 $ 2.18 19% Projected operating results: Total operating revenues $ 313,000 $ 323,000 $ 318,000 $ 272,420 17% Data center revenue 305,000 315,000 310,000 264,578 17% General and administrative expenses 30,000 32,000 31,000 27,842 11% Adjusted EBITDA(3) 153,000 158,000 155,500 129,634 20% Guidance drivers: Annual rental churn rate 6.0% 8.0% 7.0% 5.6% Cash rent growth on data center renewals 2.0% 5.0% 3.5% 2.9% Capital expenditures: Data center expansion $ 95,000 $ 110,000 $ 102,500 $ 84,312 Non-recurring investments 10,000 15,000 12,500 12,527 Tenant improvements 5,000 10,000 7,500 4,512 Recurring capital expenditures 5,000 10,000 7,500 4,429 Total capital expenditures $ 115,000 $ 145,000 $ 130,000 $ 105,780 (1) Implied growth is based on the midpoint of 2015 guidance. (2) 2014 FFO was adjusted to exclude non-recurring items, including a benefit from real estate tax accrual true-up and charges for software impairment. (3) 2014 Adjusted EBITDA was reported as $133,281 and was also adjusted to exclude a $3,647 benefit from a real estate tax accrual true-up. 24 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Appendix Definitions 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. 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 undepreciated land 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. FFO attributable to common shares and units represents FFO less preferred stock dividends declared during the period. 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. 25 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

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: Plus: Amortization of deferred financing costs Plus: Non-cash compensation Plus: Non-real estate depreciation Plus: Impairment charges Plus: Below market debt amortization Less: Straight line rents adjustment Less: Amortization of above and below market leases Less: Recurring capital expenditures Less: Tenant improvements Less: Capitalized leasing costs 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 expense to EBITDA as well as adjusting for the impact of impairment charges, gains or losses from sales of property and undepreciated land and 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. 26 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Appendix Net Operating Income (“NOI”) and Cash NOI – NOI, and cash NOI are supplemental measures for the operating performance of the company’s portfolio. NOI is operating revenues less operating expenses and adjusted for items such as depreciation and amortization, general and administrative expenses, transaction costs and litigation expenses. Cash NOI is NOI less straight-line rents and above and below market rent amortization. Data Center Net Rentable Square Feet (“NRSF”) Both occupied and available data center NRSF includes a factor to account for a customer’s proportionate share of 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. Stabilized and Pre-Stabilized NRSF Data center projects and facilities that recently have been developed and are in the initial lease-up phase are classified as pre-stabilized NRSF until they reach 85% occupancy or have been in service for 24 months. Pre-stabilized projects and facilities become stabilized operating properties at the earlier of achievement of 85% occupancy or 24 months after development completion and are included in the stabilized operating NRSF. Annualized Rent Monthly contractual rent under existing commenced customer leases as of quarter-end, multiplied by 12. This amount reflects total annualized base rent before any one-time or non-recurring rent abatements and excludes power revenue, interconnection revenue and operating expense reimbursement. NRSF Under Construction Represents NRSF for which substantial activities are ongoing to prepare the property for its intended use following development. The NRSF reflects managements estimate of engineering drawings and required support space and is subject to change based on final demising of space. Estimated costs of completion are based on actual costs at quarter-end and management’s estimate of remaining projects costs. 27 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX

Appendix NRSF Held for Development Represents incremental data center capacity that may be constructed in existing facilities and entitled land in our portfolio that requires significant capital investment in order to develop new data center facilities. In addition to entitled land, we may develop an additional 100,000 NRSF at NY2 upon our receipt of the necessary entitlements. Turn-Key Same Store Includes turn-key data center space that was leased or available to be leased to our colocation customers as of December 31, 2013, at each of our properties, and excludes powered shell data center space, SV3 data center space, office and light-industrial space and space for which development was completed and became available to be leased after December 31, 2013. The turn-key same store space as of December 31, 2013, is 1,067,665 NRSF. We track same store on a computer room basis within each data center facility. Monthly Recurring Revenue per Cabinet Equivalent Represents the turn-key monthly recurring colocation revenue (“MRR”) per cabinet equivalent billed. MRR is defined as recurring contractual revenue under existing commenced customer leases. MRR per cabinet equivalent is calculated as (current quarter MRR/3) divided by ((quarter-end cabinet equivalents billed plus prior quarter-end cabinet equivalents billed)/2). Cabinet equivalents are calculated as cage-usable square feet (turn-key leased NRSF/NRSF factor) divided by 25. Data Center Leasing Metrics Rental Churn Rate – represents data center leases which are not renewed or are terminated during the period. Rental churn is calculated based on the GAAP annualized rent of data center expired leases terminated in the period, compared with total GAAP annualized rent at the beginning of the period. Cash and GAAP Rent Growth – represents the increase in rental rates on renewed data center leases signed during the period, as compared with the previous rental rates for the same space. Cash and GAAP rent growth is calculated based on annualized rent from the renewed data center license compared to annualized rent from the expired data center license. 28 OVERVIEW FINANCIAL STATEMENTS OPERATING PORTFOLIO DEVELOPMENT CAPITAL STRUCTURE Components of NAV 2015 GUIDANCE APPENDIX