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Table of Contents
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 FORM 10-K
(Mark One):
Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.
For the fiscal year ended December 31, 2021
Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.
For the transition period from              to             
Commission File Number: 001-14195
 American Tower Corporation
(Exact name of registrant as specified in its charter)
Delaware 65-0723837
(State or other jurisdiction of
Incorporation or Organization)
 (I.R.S. Employer
Identification No.)
116 Huntington Avenue
Boston, Massachusetts 02116
(Address of principal executive offices)
Telephone Number (617375-7500
(Registrant’s telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:
Title of each Class Trading Symbol(s)Name of exchange on which registered
Common Stock, $0.01 par value AMTNew York Stock Exchange
1.375% Senior Notes due 2025AMT 25ANew York Stock Exchange
1.950% Senior Notes due 2026AMT 26BNew York Stock Exchange
0.450% Senior Notes due 2027AMT 27CNew York Stock Exchange
0.400% Senior Notes due 2027AMT 27DNew York Stock Exchange
0.500% Senior Notes due 2028AMT 28ANew York Stock Exchange
0.875% Senior Notes due 2029AMT 29BNew York Stock Exchange
0.950% Senior Notes due 2030AMT 30CNew York Stock Exchange
1.000% Senior Notes due 2032AMT 32New York Stock Exchange
1.250% Senior Notes due 2033AMT 33New York Stock Exchange
Securities registered pursuant to Section 12(g) of the Act:
None
Indicate by check mark if the registrant is a well known seasoned issuer, as defined in Rule 405 of the Securities Act:    Yes      No  
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act:    Yes      No  
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days:    Yes      No  
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes      No  
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check One):
Large accelerated filer   Accelerated filer 
Non-accelerated filer   Smaller reporting company 
Emerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   
Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (§15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.       
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act):    Yes      No  
The aggregate market value of the voting and non-voting common stock held by non-affiliates of the registrant as of June 30, 2021 was $122.5 billion, based on the closing price of the registrant’s common stock as reported on the New York Stock Exchange as of the last business day of the registrant’s most recently completed second quarter.
As of February 17, 2022, there were 455,884,806 shares of common stock outstanding.
 DOCUMENTS INCORPORATED BY REFERENCE
Portions of the definitive proxy statement (the “Definitive Proxy Statement”) to be filed with the Securities and Exchange Commission relative to the registrant’s 2022 Annual Meeting of Stockholders are incorporated by reference into Part III of this Report.


Table of Contents

AMERICAN TOWER CORPORATION
TABLE OF CONTENTS
FORM 10-K ANNUAL REPORT
FISCAL YEAR ENDED DECEMBER 31, 2021
  Page
PART I
ITEM 1.
ITEM 1A.
ITEM 1B.
ITEM 2.
ITEM 3.
ITEM 4.
PART II
ITEM 5.
ITEM 6.
ITEM 7.
ITEM 7A.
ITEM 8.
ITEM 9.
 














i

Table of Contents

AMERICAN TOWER CORPORATION
TABLE OF CONTENTS—(Continued)
FORM 10-K ANNUAL REPORT
FISCAL YEAR ENDED DECEMBER 31, 2021
  Page
ITEM 9A.
ITEM 9C.
PART III
ITEM 10.
ITEM 11.
ITEM 12.
ITEM 13.
ITEM 14.
PART IV
ITEM 15.
ITEM 16.
F-1
 
ii

Table of Contents

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
This Annual Report on Form 10-K (this “Annual Report”) contains statements about future events and expectations, or forward-looking statements, all of which are inherently uncertain. We have based those forward-looking statements on our current expectations and projections about future results. When we use words such as “anticipates,” “intends,” “plans,” “believes,” “estimates,” “expects” or similar expressions, we are making forward-looking statements. Examples of forward-looking statements include, but are not limited to, future prospects of growth in the communications infrastructure leasing industry, the effects of consolidation among companies in our industry and among our customers and other competitive and financial pressures, our ability to maintain or increase our market share, our plans to fund our future liquidity needs, our substantial leverage and debt service obligations, our future financing transactions, our future operating results, the level of future expenditures by companies in this industry and other trends in this industry, changes in zoning, tax and other laws and regulations and administrative and judicial decisions, economic, political and other events, particularly those relating to our international operations, our future capital expenditure levels, our expectations regarding the impacts of the coronavirus (“COVID-19”) pandemic and actions in response to the COVID-19 pandemic on our business and our operating results, the expected impact of the CoreSite Acquisition (as defined in this Annual Report) on our business, including our ability to successfully integrate the CoreSite assets or utilize such assets to their full capacity, the impact of technology changes on our industry and our business, our ability to remain qualified for taxation as a real estate investment trust (REIT), the amount and timing of any future distributions including those we are required to make as a REIT, natural disasters and similar events, technology failures, including cybersecurity and data privacy incidents, and our ability to protect our rights to the land under our towers and buildings in which our data centers are located. These statements are based on our management’s beliefs and assumptions, which in turn are based on currently available information. These assumptions could prove inaccurate. These forward-looking statements may be found under the captions “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” as well as in this Annual Report generally.
You should keep in mind that any forward-looking statement we make in this Annual Report or elsewhere speaks only as of the date on which we make it. New risks and uncertainties arise from time to time, and it is impossible for us to predict these events or how they may affect us. In any event, these and other important factors, including those set forth in Item 1A of this Annual Report under the caption “Risk Factors,” may cause actual results to differ materially from those indicated by our forward-looking statements. We have no duty, and do not intend, to update or revise the forward-looking statements we make in this Annual Report, except as may be required by law. In light of these risks and uncertainties, you should keep in mind that the future events or circumstances described in any forward-looking statement we make in this Annual Report or elsewhere might not occur. References in this Annual Report to “we,” “our” and the “Company” refer to American Tower Corporation and its predecessor, as applicable, individually and collectively with its subsidiaries as the context requires.
iii

Table of Contents
PART I
ITEM 1.BUSINESS
Overview
We are one of the largest global real estate investment trusts and a leading independent owner, operator and developer of multitenant communications real estate. Our primary business is the leasing of space on communications sites to wireless service providers, radio and television broadcast companies, wireless data providers, government agencies and municipalities and tenants in a number of other industries. We refer to this business as our property operations, which accounted for 97% of our total revenues for the year ended December 31, 2021. We also offer tower-related services in the United States, which we refer to as our services operations. These services include site application, zoning and permitting and structural analysis, which primarily support our site leasing business, including the addition of new tenants and equipment on our sites. Our customers include our tenants, licensees and other payers.
Since inception, we have grown our communications real estate portfolio through acquisitions, long-term lease arrangements and site development. Our portfolio primarily consists of towers that we own and towers that we operate pursuant to long-term lease arrangements, as well as distributed antenna system (“DAS”) networks, which provide seamless coverage solutions in certain in-building and outdoor wireless environments. In addition to the communications sites in our portfolio, we manage rooftop and tower sites for property owners under various contractual arrangements. We also hold other telecommunications infrastructure, fiber and property interests that we lease primarily to communications service providers and third-party tower operators, and, as discussed further below, we hold a portfolio of highly interconnected data center facilities and related assets in the United States that we lease primarily to enterprises, network operators, cloud providers and supporting service providers.
In 2021, we added approximately 31,000 communications sites to our portfolios in Latin America and Europe and launched operations in Spain as part of our transaction with Telxius Telecom, S.A. (“Telxius,” and the acquisition, the “Telxius Acquisition,” as further discussed in Item 7 of this Annual Report under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Overview”). In addition, we launched operations in the Philippines through the construction of new sites therein and in Bangladesh through the acquisition of a controlling interest in Kirtonkhola Tower Bangladesh Limited (the “Bangladesh Acquisition”). As of December 31, 2021, our communications real estate portfolio of 220,131 communications sites included 43,308 communications sites in the U.S. & Canada, 75,725 communications sites in Asia-Pacific, 22,165 communications sites in Africa, 30,041 communications sites in Europe and 48,892 communications sites in Latin America, as well as urban telecommunications assets, including fiber, in Argentina, Brazil, Colombia, India, Mexico and South Africa and other property interests in Australia, Canada and the United States.
In December 2021, we completed the acquisition of CoreSite Realty Corporation (“CoreSite”), consisting of over 20 data center facilities and related assets in eight United States markets, for total consideration of $10.4 billion, including the assumption and repayment of CoreSite’s existing debt (the “CoreSite Acquisition”). As of December 31, 2021, our data center portfolio consisted of 27 data center facilities across ten United States markets, including the assets acquired as part of the CoreSite Acquisition, as well as our previously acquired data center facilities.
In May 2021 and June 2021, in connection with the funding of the Telxius Acquisition, we entered into agreements with Caisse de dépôt et placement du Québec (“CDPQ”) and Allianz insurance companies and funds managed by Allianz Capital Partners GmbH, including the Allianz European Infrastructure Fund (collectively, “Allianz”), for CDPQ and Allianz to acquire 30% and 18% noncontrolling interests, respectively, in subsidiaries whose holdings consist of our operations in France, Germany, Poland and Spain (such subsidiaries collectively, “ATC Europe,” and the transactions, the “ATC Europe Transactions”). We completed the ATC Europe Transactions in September 2021 for total aggregate consideration of 2.6 billion Euros (“EUR”) (approximately $3.1 billion at the date of closing). After the completion of the ATC Europe Transactions, we hold a 52% controlling ownership interest in ATC Europe.
We operate as a real estate investment trust for U.S. federal income tax purposes (“REIT”). Accordingly, we generally are not required to pay U.S. federal income taxes on income generated by our REIT operations, including the income derived from leasing space on our towers and in our data centers, as we receive a dividends paid deduction for distributions to stockholders that generally offsets our REIT income and gains. However, we remain obligated to pay U.S. federal income taxes on earnings from our domestic taxable REIT subsidiaries (“TRSs”). In addition, our international assets and operations, regardless of their classification for U.S. tax purposes, continue to be subject to taxation in the jurisdictions where those assets are held or those operations are conducted.
The use of TRSs enables us to continue to engage in certain businesses and jurisdictions while complying with REIT qualification requirements. We may, from time to time, change the election of previously designated TRSs to be included as part of the REIT. As of December 31, 2021, our REIT-qualified businesses included our U.S. tower leasing business, a majority of our U.S. indoor DAS networks business, our Services and Data Centers segments, as well as most of our operations in
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Canada, Costa Rica, France, Germany, Mexico and Nigeria. In January 2022, a majority of our operations in Ghana, Kenya, South Africa and Uganda became part of the REIT.
During the fourth quarter of 2021, as a result of the CoreSite Acquisition, we updated our reportable segments to add a Data Centers segment. The Data Centers segment is included within our property operations. We will now report our results in seven segments – U.S. & Canada property (which includes all assets in the United States and Canada, other than our data center facilities and related assets), Asia-Pacific property, Africa property, Europe property, Latin America property, Data Centers and Services. We believe this change provides greater visibility into our operating segments and aligns our reporting with management’s current approach of allocating costs and resources, managing growth and profitability and assessing the operating performance of our business segments. This change applies to our business operations results beginning with the fourth quarter of 2021 and had no impact on our consolidated financial statements for any prior periods. Historical financial information included in this Annual Report has not been adjusted as the amounts attributable to data center assets were insignificant as prior to the fourth quarter of 2021, we owned one data center.    
Products and Services
Property Operations
Our property operations accounted for 97%, 99% and 98% of our total revenues for the years ended December 31, 2021, 2020 and 2019, respectively. Our revenue is primarily generated from tenant leases. Our tenants lease space on our communications real estate, where they install and maintain their equipment. Rental payments vary considerably depending upon numerous factors, including, but not limited to, amount, type and position of tenant equipment on the tower, remaining tower capacity and tower location. Our costs typically include ground rent (which is primarily fixed under long-term lease agreements with annual cost escalations) and power and fuel costs, some or all of which may be passed through to our tenants, as well as property taxes and repair and maintenance expenses. Our property operations have generated consistent growth in revenue and typically have low cash flow volatility due to the following characteristics:
Long-term tenant leases with contractual rent escalations. In general, our tenant leases for our communications sites with wireless carriers have initial non-cancellable terms of five to ten years with multiple renewal terms, with provisions that periodically increase the rent due under the lease, typically annually, based on a fixed escalation percentage (averaging approximately 3% in the United States) or an inflationary index in most of our international markets, or a combination of both. Based upon foreign currency exchange rates and the tenant leases in place as of December 31, 2021, we expect to generate over $61 billion of non-cancellable tenant lease revenue over future periods, before the impact of straight-line lease accounting.
Consistent demand for our sites. As a result of rapidly growing usage of mobile data and other wireless services and the corresponding wireless industry capital spending trends in the markets we serve, we anticipate consistent demand for our communications sites. We believe that our global asset base positions us well to benefit from the increasing proliferation of advanced wireless devices and the increasing usage of high bandwidth applications on those devices. We have the ability to add new tenants and new equipment for existing tenants on our sites, which typically results in incremental revenue and modest incremental costs. Our site portfolio and our established tenant base provide us with a solid platform for new business opportunities, which has historically resulted in consistent and predictable organic revenue growth.
High lease renewal rates. Our tenants tend to renew leases because suitable alternative sites may not exist or be available and repositioning a site in their network may be expensive and may adversely affect network quality. Historically, churn has averaged approximately 1% to 2% of tenant billings per year. We define churn as tenant billings lost when a tenant cancels or does not renew its lease or, in limited circumstances, when the lease rates on existing leases are reduced. We derive our churn rate for a given year by dividing our tenant billings lost on this basis by our prior-year tenant billings. As discussed in Item 7 of this Annual Report under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Overview,” we experienced elevated levels of churn in recent years due to carrier consolidation-driven churn in India. We anticipate that our churn rate in our Asia-Pacific property segment will moderate over time, however, in the immediate term, we believe that our churn rate may remain elevated as, among other things, our tenants in India evaluate how best to comply with the recent court rulings by the Supreme Court of India and determine their obligations under payment plans for the adjusted gross revenue (“AGR”) fees and charges prescribed by such court, as further discussed in Item 1A of this Annual Report under the caption “Risk Factors—Our business, and that of our customers, is subject to laws, regulations and administrative and judicial decisions, and changes thereto, that could restrict our ability to operate our business as we currently do or impact our competitive landscape.” Additionally, we expect that our churn rate in our U.S. & Canada property segment will be elevated for a period of several years due to contractual lease cancellations
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and non-renewals pursuant to the terms of our master lease agreement with T-Mobile US, Inc. (“T-Mobile,” and the agreement, the “T-Mobile MLA”) entered into in September 2020.
High operating margins. Incremental operating costs associated with adding new tenants or equipment to an existing communications site are relatively minimal. Therefore, as tenants or equipment are added, the substantial majority of incremental revenue flows through to gross margin and operating profit. In addition, in many of our international markets, certain expenses, such as ground rent or power and fuel costs, are reimbursed or shared by our tenant base.
Low maintenance capital expenditures. On average, we require relatively low amounts of annual capital expenditures to maintain our communications sites.
Our property business includes the operation of communications sites and managed networks, the leasing of property interests and, in select markets, the operation of fiber, the operation of data centers and the provision of backup power through shared generators. Our presence in a number of markets at different relative stages of wireless development provides us with significant diversification and long-term growth potential. Our property segments accounted for the following percentage of consolidated total revenue for the years ended December 31,:
202120202019
U.S. & Canada52 %56 %55 %
Asia-Pacific13 %14 %16 %
Africa11 %11 %%
Europe%%%
Latin America16 %16 %18 %
Data Centers%— %— %
Communications Sites. Approximately 95% of revenue in our property segments was attributable to our communications sites, excluding DAS networks, for each of the years ended December 31, 2021, 2020 and 2019.
We lease space on our communications sites to tenants providing a diverse range of communications services, including cellular voice and data, broadcasting, mobile video and a number of other applications. In addition, in many of our international markets, we receive pass-through revenue from our tenants to cover certain costs, including power and fuel costs and ground rent. Our top tenants by revenue for each property segment are as follows for the year ended December 31, 2021:
U.S. & Canada: AT&T Inc. (“AT&T”); T-Mobile; and Verizon Wireless accounted for an aggregate of 88% of U.S. & Canada property segment revenue.
Asia-Pacific: Vodafone Idea Limited; Bharti Airtel Limited (“Airtel”); and Reliance Jio accounted for an aggregate of 89% of Asia-Pacific property segment revenue.
Africa: Airtel; and MTN Group Limited (“MTN”) accounted for an aggregate of 73% of Africa property segment revenue.
Europe: Telefónica S.A. (“Telefónica”); and Bouygues accounted for an aggregate of 74% of Europe property segment revenue.
Latin America: AT&T; Telefónica; and América Móvil accounted for an aggregate of 60% of Latin America property segment revenue.
Accordingly, we are subject to certain risks, as set forth in Item 1A of this Annual Report under the caption “Risk Factors—A substantial portion of our revenue is derived from a small number of customers, and we are sensitive to adverse changes in the creditworthiness and financial strength of our customers.” In addition, we are subject to risks related to our international operations, as set forth under the caption “Risk Factors—Our foreign operations are subject to economic, political and other risks that could materially and adversely affect our revenues or financial position, including risks associated with fluctuations in foreign currency exchange rates.”
Managed Networks, Fiber and Related Assets, Data Centers and Related Assets, Property Interests and Shared Generators. In addition to our communications sites, we also own and operate several types of managed network solutions, provide communications site management services to third parties, manage and lease property interests under carrier or other third-party communications sites, provide the right to use fiber, operate data center facilities and provide back-up power sources to tenants at our sites. The balance of our property segment revenue not attributable to our communications sites was attributable to these items.
Managed Networks. We own and operate DAS networks in the United States and certain international markets. We obtain rights from property owners to install and operate in-building DAS networks, and we grant rights to wireless service providers to attach their equipment to our installations. We also offer a small portfolio of outdoor DAS networks as a complementary shared infrastructure solution for our tenants in the United States and in certain
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international markets. Typically, we have designed, built and operated our outdoor DAS networks in areas in which zoning restrictions or other barriers may prevent or delay deployment of more traditional wireless communications sites, such as macro tower sites. We also hold lease rights and easement interests on rooftops capable of hosting communications equipment in locations where towers are generally not a viable solution based on area characteristics. In addition, we provide management services to property owners in the United States who elect to retain full rights to their property while simultaneously marketing the rooftop for wireless communications equipment installation. As the demand for advanced wireless services in urban markets evolves, we continue to evaluate a variety of infrastructure solutions, including small cells and other network architectures that may support our tenants’ networks in these areas.
Fiber and Related Assets. We own and operate fiber and related assets in certain international markets. We currently provide the right to use such fiber and related assets to communications and internet service providers and third-party operators to support their telecommunications infrastructure. We expect to continue to evaluate opportunities to invest selectively in and expand these and other similar assets in the future as part of advanced network deployments.
Data Centers and Related Assets. As a result of our recent data center acquisitions, we own and operate data center facilities and related assets in the United States, which consist of specialized and secure buildings that house networking, storage and communications technology infrastructure, including servers, storage devices, switches, routers and fiber optic transmission equipment. These buildings are designed to provide the power, cooling and network connectivity necessary to efficiently operate this equipment. Data centers located at points where many communications networks converge can also function as interconnection hubs where customers are able to connect to multiple networks, cloud companies and other service providers to exchange traffic and interoperate with each other.
Property Interests. We own portfolios of property interests in Australia, Canada and the United States, including land under carrier or other third-party communications sites, which provide recurring cash flow under complementary leasing arrangements.
Shared Generators. We have contracts with certain of our tenants in the United States pursuant to which we provide access to shared backup power generators.
Services Operations
We offer tower-related services in the United States, including site application, zoning and permitting and structural analysis services. Our services operations primarily support our site leasing business, including through the addition of new tenants and equipment on our sites. This segment accounted for 3%, 1% and 2% of our total revenue for the years ended December 31, 2021, 2020 and 2019, respectively.
Site Application, Zoning and Permitting. We engage in site application services on our own behalf in connection with our tower development projects, as well as on behalf of our tenants. We typically work with our tenants’ engineers to determine the geographic areas where new communications sites will best address the tenants’ needs and meet their coverage objectives. Once a new site is identified, we acquire the rights to the land or structure on which the site will be constructed, and we manage the permitting process to ensure all necessary approvals are obtained to construct and operate the communications site.
Structural Analysis. We offer structural analysis services to wireless carriers in connection with the installation of their communications equipment on our towers. Our team of engineers can evaluate whether a tower structure can support the additional burden of the new equipment or if an upgrade is needed, which enables our tenants to better assess potential sites before making an installation decision. Our structural analysis capabilities enable us to provide higher quality service to our existing tenants by, among other things, reducing the time required to achieve on-air readiness, while also providing opportunities to offer structural analysis services to third parties.
Strategy
Operational Strategy
As the use of wireless services on handsets, tablets and other advanced mobile devices grows and evolves, there is a corresponding increase in demand for the communications infrastructure required to deploy current and future generations of wireless communications technologies. To capture this demand, our primary operational focus is to (i) increase the occupancy of our existing communications real estate portfolio to support global connectivity, (ii) invest in and selectively grow our communications real estate portfolio, (iii) further improve our operational performance and efficiency, including through platform expansion initiatives, and (iv) maintain a strong balance sheet. We believe these efforts to meet our customers’ needs will support and enhance our ability to capitalize on the growth in demand for wireless infrastructure. In addition, we expect to explore new opportunities to enhance or extend our shared communications infrastructure businesses, including those that may make our assets incrementally more attractive to new customers, or to existing customers for new uses, and those that increase our operational efficiency.
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Increase the occupancy of our existing communications real estate portfolio to support global connectivity. We believe that our highest incremental returns will be achieved by leasing additional space on our existing communications sites. Increasing demand for wireless services in our served markets has resulted in significant capital spending by major wireless carriers and other connectivity providers. As a result, we anticipate growing demand for our communications sites because they are attractively located and typically have capacity available for additional tenants and equipment. In the United States, incremental carrier network activity is being driven by 4G network densification initiatives as well as the early stages of multiple concurrent 5G network deployments. In our international markets, carriers are increasingly deploying more advanced network technologies such as 4G and, in the case of our international markets with more mature network technology, 5G, while continuing to selectively augment legacy networks. We believe that the majority of our towers have capacity for additional tenants and that substantially all of our towers that are currently at or near full structural capacity can be upgraded or augmented to meet future tenant demand with relatively modest capital investment. Therefore, we will continue to target our sales and marketing activities to increase the utilization and return on investment of our existing communications sites.
Invest in and selectively grow our communications real estate portfolio to meet our customers’ needs. We seek opportunities to invest in and grow our operations through our capital expenditure program and acquisitions. A significant portion of our inorganic growth has been focused on properties with lower initial tenancy because we believe that over time we can significantly increase tenancy levels, and therefore, drive strong returns on those assets. More recently, we have invested in strategic data center assets, including through the CoreSite Acquisition, which we believe can drive strong, recurring growth and also meaningfully enhance the value of our existing communications tower real estate through emerging edge compute opportunities in the future.
Further improve our operational performance and efficiency. We continue to seek opportunities to improve our operational performance throughout the organization. This includes investing in our systems and people as we strive to improve efficiency and provide superior service to our customers. To achieve this, we intend to continue to focus on customer service initiatives, such as reducing cycle times for key functions, including lease processing and tower structural analysis. We are also focused on developing and implementing renewable power solutions across our footprint to reduce our reliance on fossil fuels and help improve the overall efficiency of the communications infrastructure and wireless industries through our sustainability and platform expansion initiatives. We also expect to explore additional ways to use our platform expansion initiatives to enhance the efficiency of our operations over time.
Maintain a strong balance sheet. We remain committed to disciplined financial policies, which we believe result in our ability to maintain a strong balance sheet and will support our overall strategy and focus on asset growth and operational excellence. As a result of these policies, we currently have investment grade credit ratings. We continue to focus on maintaining a robust liquidity position and, as of December 31, 2021, had $6.1 billion of available liquidity. We believe that our investment grade credit ratings provide us consistent access to the capital markets and our liquidity provides us the ability to continue to invest in growing and augmenting our business.
Capital Allocation Strategy
The objective of our capital allocation strategy is to simultaneously increase adjusted funds from operations per share and our return on invested capital over the long term. To maintain our qualification for taxation as a REIT, we are required annually to distribute an amount equal to at least 90% of our REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain) to our stockholders. After complying with our REIT distribution requirements, we plan to continue to allocate our available capital among investment alternatives that meet or exceed our return on investment criteria, while taking into account the repayment of debt consistent with our financial policies.
Capital expenditure program. We expect to continue to invest in and expand our existing communications real estate portfolio through our capital expenditure program. This includes capital expenditures associated with site maintenance, increasing the capacity of our existing sites and projects such as new site and data center facility construction, land interest acquisitions and power solutions.
Acquisitions. We intend to continue to pursue acquisitions of communications sites and other telecommunications infrastructure in our existing or new markets where we can meet or exceed our risk-adjusted return on investment criteria. The risk-adjusted hurdle rates used to evaluate acquisition opportunities consider additional factors such as the country and counterparties involved, investment and economic climate, legal and regulatory conditions and industry risk, among others.
Return excess capital to stockholders. If we have excess capital available after funding (i) our required distributions, (ii) capital expenditures, (iii) the repayment of debt consistent with our financial policies and (iv) anticipated future investments, including acquisition and select platform expansion opportunities, we will seek to return such excess capital to stockholders, including through our stock repurchase programs.
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International Growth Strategy
We believe that, in certain international markets, we can create substantial value by either establishing a new, or expanding our existing, communications real estate leasing business. Therefore, we expect we will continue to seek international growth opportunities where we believe our risk-adjusted return objectives can be achieved. We strive to maintain a diversified approach to our international growth strategy by operating in a geographically diverse array of markets in a variety of stages of wireless network development. Our international growth strategy includes a disciplined, individualized market evaluation, in which we conduct the following analyses, among others:
Country analysis. Prior to entering a new market, we conduct an extensive review of the country’s historical and projected macroeconomic fundamentals, including inflation and foreign currency exchange rate trends, demographics, capital markets, tax regime and investment alternatives, and the general business, political and legal environments, including property rights and regulatory regime.
Wireless industry analysis. To confirm the presence of sufficient demand to support an independent tower leasing model, we analyze the competitiveness of the country’s wireless market. This includes an evaluation of the industry’s pricing environment, past and potential consolidation and the stage of its wireless network development. Characteristics that result in an attractive investment opportunity include (i) multiple competitive wireless service providers who are actively seeking to invest in deploying voice and data networks and (ii) ongoing or expected deployment of incremental spectrum from recent or anticipated auctions.
Opportunity and counterparty analysis. Once an investment opportunity is identified within a geographic area with an attractive wireless industry, we conduct a multifaceted opportunity and counterparty analysis. This includes evaluating (i) the type of transaction, (ii) its ability to meet our risk-adjusted return criteria given the country and the counterparties involved, including the anticipated anchor tenant and (iii) how the transaction fits within our long-term strategic objectives, including future potential investment and expansion within the region.
Regulatory Matters
Towers, Antennas and Fiber. Our U.S. and international tower leasing businesses are subject to national, state and local regulatory requirements with respect to the registration, siting, construction, lighting, marking and maintenance of our towers. In the United States, the construction of new towers or modifications to existing towers may require pre-approval by the Federal Communications Commission (“FCC”) and the Federal Aviation Administration (“FAA”), depending on factors such as tower height and proximity to public airfields. Towers requiring pre-approval must be registered with the FCC and maintained in accordance with FAA standards. Similar requirements regarding pre-approval of the construction and modification of towers are imposed by regulators in other countries. Non-compliance with applicable tower-related requirements may lead to monetary penalties or site deconstruction orders.
Certain of our international operations are subject to regulatory requirements with respect to licensing, registration, permitting and public listings. In India, our subsidiary, ATC Telecom Infrastructure Private Limited (“ATC TIPL”), holds an Infrastructure Provider Category-I (“IP-I”) Registration Certificate issued by the Indian Ministry of Communications and Information Technology, which permits us to provide tower space to companies licensed as telecommunications service providers under the Indian Telegraph Act of 1885. As a condition to the IP-I, the Indian government has the right to take over telecommunications infrastructure in the case of emergency or war. Additionally, in 2018, ATC TIPL issued non-convertible debentures, which are listed on the National Stock Exchange of India. Although the debt is held by another subsidiary of ours and is eliminated in consolidation, ATC TIPL is still subject to the listing requirements of such exchange.
In Asia-Pacific, our subsidiaries in the Philippines and Bangladesh are required to hold a registration or license in order to establish, manage and operate passive telecommunications infrastructure services.
In Africa, our subsidiaries in Burkina Faso, Ghana, Kenya, Niger, Nigeria and Uganda are required to hold a license in order to establish and maintain passive telecommunications infrastructure services and DAS networks for communications service providers. Additionally, in Uganda, our subsidiary is subject to review for three years commencing in 2020 by a monitoring trustee regarding compliance with certain conditions of approval of our acquisition in 2019 of Eaton Towers Holdings Limited.
In Latin America, our subsidiary in Chile holds a license for the provision of passive telecommunications infrastructure and our subsidiary in Argentina holds a license for the leasing of fiber. The subsidiaries that hold our fiber business in Mexico and Brazil are also licensed and regulated as concession holders and permit holders authorized to provide telecommunications services. In many of the markets in which we operate, we are required to provide tower space to service providers on a non-discriminatory basis, subject to the negotiation of mutually agreeable terms.
Our international business operations may be subject to increased licensing fees or ownership restrictions. For example, in South Africa, the Broad-Based Black Economic Empowerment Act, 2003 (the “BBBEE Act”) has established a legislative framework for the promotion of economic empowerment of South African citizens disadvantaged by Apartheid. Accordingly,
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the BBBEE Act and related codes measure BBBEE Act compliance and good corporate practice by the inclusion of certain ownership, management control, employment equity and other metrics for companies that do business there. In Kenya, our regulator requires all holders of a commercial license to issue at least 30% of their shares to Kenyans within three years of receiving the license unless a waiver is obtained to extend such period of compliance by a year. In addition, certain municipalities have sought to impose permit fees based upon structural or operational requirements of towers and certain regional and other governmental bodies have sought to impose levies or other forms of fees. Our foreign operations may be affected if a country’s regulatory authority restricts, revokes or modifies spectrum licenses of certain wireless service providers or implements limitations on foreign ownership.
In all countries where we operate, we are subject to zoning restrictions and restrictive covenants imposed by local authorities or community organizations. While these regulations vary, they typically require tower owners or tenants to obtain approval from local authorities or community standards organizations prior to tower construction or the addition of a new antenna to an existing tower. Local zoning authorities and community residents often oppose construction in their communities, which can delay or prevent new tower construction, new antenna installation or site upgrade projects, thereby limiting our ability to respond to tenant demand. This opposition and existing or new zoning regulations can increase costs associated with new tower construction, tower modifications or additions of new antennas to a site or site upgrades, as well as adversely affect the associated timing or cost of such projects. Further, additional regulations may be adopted that cause delays or result in additional costs to us or changes in the competitive landscape that may negatively affect our business. These factors could materially and adversely affect our operations. In the United States, the Telecommunications Act of 1996 prohibits any action by state and local authorities that would discriminate between different providers of wireless services or ban altogether the construction, modification or placement of communications sites. It also prohibits state or local restrictions based on the environmental effects of radio frequency emissions to the extent the facilities comply with FCC regulations. Further, in February 2012, the United States government adopted regulations requiring that local and state governments approve modifications or colocations that qualify as eligible facilities under the regulations. 
Portions of our business are subject to additional regulations, for example, in a number of states throughout the United States, certain of our subsidiaries hold Competitive Local Exchange Carrier (CLEC) or other status, in connection with the operation of our outdoor DAS networks business. In addition, we, or our customers, may be subject to new regulatory policies in certain jurisdictions from time to time that may materially and adversely affect our business or the demand for our communications sites.
Data Centers. Our U.S. data center facilities and related assets are subject to various federal, state and local regulations, such as state and local fire and life safety regulations and Americans with Disabilities Act (“ADA”) federal requirements. If one of our properties is not in compliance with these regulations, we may be required to make significant unanticipated expenditures in order to comply with such regulations and/or pay fines or civil damage awards. Existing regulations may subsequently change or future regulations may be enacted, either of which could have a similar impact as described above, and could materially and adversely affect our operations.

Environmental Matters. Our U.S. and international operations are subject to various national, state and local environmental laws and regulations, including those relating to the management, use, storage, disposal, emission and remediation of, and exposure to, hazardous and non-hazardous substances, materials and wastes, the siting of our towers and the maintenance of our data center facilities. We may be required to obtain permits, pay additional property taxes, comply with regulatory requirements and make certain informational filings related to hazardous substances or devices used to provide power such as batteries, generators and fuel at our tower sites and/or data center facilities. With respect to our data center facilities, the presence of contamination, asbestos, mold or other air quality issues or the failure to remediate contamination, asbestos, mold or other air quality issues at our facilities may expose us to third-party liability or materially adversely affect our ability to sell, lease or develop the real estate or to borrow using the real estate as collateral. Violations of these types of regulations could subject us to fines or criminal sanctions.

Additionally, in the United States and in other countries where we operate, before constructing a new tower or adding an antenna to an existing site, we must review and evaluate the impact of the action to determine whether it may significantly affect the environment and whether we must disclose any significant impacts in an environmental assessment. If a tower or new antenna might have a material adverse impact on the environment, FCC or other governmental approval of the tower or antenna could be significantly delayed.
The U.S. Environmental Protection Agency, or EPA, and some of the states and localities in which we operate, have also enacted certain climate change laws and regulations and/or have begun regulating carbon footprints and greenhouse gas emissions and may adopt new regulations related to the use of fossil fuels or requiring the use of alternative fuel or renewable energy sources to power energy resources that serve our data centers. Efforts to support and enhance renewable electricity generation may increase our costs of electricity above those that would be incurred through procurement of conventional
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electricity. Our data centers require and consume significant amounts of power, including electricity generated by the burning of fossil fuels. These laws, regulations and stakeholder requests could limit our ability to develop new facilities or result in substantial compliance, maintenance, repair, retrofit and construction costs, including capital expenditures for environmental control facilities and other new equipment. Changes in regulations that affect electric power providers, such as regulations related to the control of greenhouse gas emissions or other climate change-related matters, could adversely affect the costs of electric power and increase our operating costs, which could adversely affect our business, financial condition and results of operations or those of our customers.

Health and Safety. In the United States and in other countries where we operate, we are subject to various national, state and local laws regarding employee health and safety, including protection from radio frequency exposure and air quality issues. Additionally, and in response to various national, state and local laws and guidance enacted in response to the ongoing COVID-19 pandemic, we implemented work-from-home arrangements and travel restrictions for our employees where practicable, as well as and other modifications to our business practices.
Competition
Our industry is highly competitive. We compete, both for new business and for the acquisition of assets, with other public tower companies, such as Crown Castle International Corp., SBA Communications Corporation, Telesites S.A.B. de C.V. and Cellnex Telecom, S.A., wireless carrier tower consortia such as Indus Towers Limited and private tower companies, private equity sponsored firms, carrier-affiliated tower companies, independent wireless carriers, tower owners, broadcasters and owners of non-communications sites, including rooftops, utility towers, water towers and other alternative structures. Our data center business also competes with a variety of companies offering similar data center solutions and services, including space, power, interconnection and development services. We believe that location and capacity, network and/or interconnection density, price, quality and speed of service have been, and will continue to be, significant competitive factors affecting owners, operators and managers of communications sites and data center facilities.
Our services business competes with a variety of companies offering individual, or combinations of, competing services. The field of competitors includes site application consultants, zoning consultants, real estate firms, right-of-way consultants, structural engineering firms, tower owners/managers, telecommunications equipment vendors who can provide turnkey site development services through multiple subcontractors and our tenants’ personnel. We believe that our tenants base their decisions for services on various criteria, including a company’s experience, local reputation, price and time for completion of a project.
For more information on demand trends in our industry, see Item 7 of this Annual Report under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Overview.”
Human Capital Resources
As of December 31, 2021, we employed 6,378 full-time individuals, including 2,291 employees based in the United States and 4,087 employees based internationally. Our teams representing our over 20 countries around the world are our most important assets and fundamental to our success. Aligned with our business strategy, our human capital management strategy focuses on developing and delivering solutions to attract, develop, engage and retain top diverse talent in each of the countries where we operate. We consider our employee relations to be good. Our Chief Sustainability Officer regularly reports to the Nominating and Corporate Governance Committee of our Board of Directors on our initiatives related to human capital management.
Employee Engagement. In 2021, our employees completed our biennial company-wide engagement survey to provide feedback on our company in nine key areas. The survey was completed by 91% of our employees globally. All of the nine areas measured scored over 70% in favorability. Of note, teamwork and leadership both received an 89% favorability score, employee engagement received an 87% favorability score and diversity and inclusion received an 83% favorability score. Additionally, our COVID-19 response received a 91% favorability score. The questions with the highest favorable ratings were focused on our culture, values and ethics.
Diversity, Equity and Inclusion. Diversity, equity and inclusion are fundamental considerations and values for us in conducting business. A critical factor in our success is ensuring that each of these remains at the core of our business culture, infusing fresh ideas, helping us remain connected to our customers in a dynamic global market and ensuring mutual respect guides us in our interactions both internally and externally. We have adopted a Global Human Rights Statement, which can be found on our website.
Our Board of Directors is a diverse group with respect to traditional diversity metrics such as gender, race and national origin, as well as professional background and skills, with four members of our board identifying as female and five identifying as part of a minority group. We are also committed to ensuring diverse representation among our employees. In 2021, 38% of all
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employees promoted globally were female, which is greater than the female representation in our workforce of 28%. And as of December 31, 2021, nearly 40% of management-level positions in the United States were also held by women.
Additionally, we have implemented several initiatives designed to help address social injustice and enhance our diversity. These include pledges from the American Tower Foundation of (i) $1.0 million for grants to organizations recommended by our Social Justice Committee to counter systemic racism and (ii) $1.0 million for scholarship funds at two Historically Black Colleges and Universities. In 2021, we created a new senior role, Chief Diversity, Equity and Inclusion Officer, tasked with leading our diversity, equity and inclusion strategy by introducing new initiatives and best practices, including working with each region to develop relevant representation, development and recruitment goals and launching a company-wide resource center for our employees.
Talent Development and Recruitment. As a critical investment in our capacity to provide our customers with outstanding support and customer service, we offer a variety of development opportunities unique to each market to cultivate our talent throughout our global organization. For individual contributors, we have 8,700 resources in up to five languages that focus on job-specific training and general topics, such as productivity, collaboration and project management. We create and customize courses to meet regional needs and update these courses regularly to address changing marketplace dynamics and employee interests.
Developing our managers is critical to our success, and over 30,000 resources and tools are provided to all levels of management. For example, the Management Development at American Tower program provides continuous development opportunities through training led by American Tower leaders. Managers learn tools and best practices that enable both management and team success, and that build and strengthen competencies to better respond to the needs of a growing and increasingly complex organization. Our annual Advanced Leadership Development Program, in collaboration with the INSEAD executive education program, provides our next generation leaders in Latin America, Europe and Africa with a twelve-week intensive workshop to enhance management and leadership skills. The Leadership Excellence at American Tower Program supports global senior leaders’ development through its partnership with the Massachusetts Institute of Technology. Participants learn from leading experts on topics like global strategy and leading in uncertain times. We also have a comprehensive talent-management review process to develop future leaders and ensure effective succession planning.
Our recruiting efforts consistently include strategies to build diverse candidate pipelines and promote a culture that supports a diverse team of global employees. We are proud of our Leadership Development Program, which provides a recruitment opportunity for business school students, who are able to learn about different aspects of our business through regular rotational assignments. Further, with respect to our Leadership Development Program, as of December 31, 2021, 67% of our hires identified as part of a minority group and 33% identified as female. We have also increased our recruiting efforts with Historically Black Colleges and Universities as well as other recruiting efforts to build a diverse talent pipeline.
Workplace Safety. We are committed to the safety of our employees and surrounding communities. Depending on the role, team members are required to pass and complete regular safety training courses and follow specific tower and site safety protocols using complex operational manuals. A key component of our culture is a strong commitment to incident reporting and corrective actions, as well as a comprehensive program for ensuring vendor compliance with safety standards and certifications. Our strict adherence to the rigorous standards set forth by the relevant government agencies and other authorities, such as the Telecommunications Infrastructure Registered Apprenticeship Program and Telecommunications Industry Association, is critical to ensuring our towers are structurally safe for field personnel, vendors, customers and communities. In 2021, we created a new senior role, Chief Security Officer, tasked with helping to ensure the safety and security of our employees globally, as well as implementing best in class security protocols.
Health and Wellness. We offer medical and parental leave benefits to full-time employees across all markets, with some local variation. As a result of the effects of the COVID-19 pandemic, we conduct wellness check-ins and offer resources to support our employees’ mental health and well-being, including access to a free Employee Assistance Program, which offers confidential assistance on a wide range of issues. We also offer market competitive benefits in all locations and, in 2021, introduced a behavioral health benefit in the United States to support employees’ mental well-being.
Executive Officers
For information about our Executive Officers, see Item 10 of this Annual Report under the caption “Directors, Executive Officers and Corporate Governance.”
Available Information
Our internet website address is www.americantower.com. Information contained on our website is not incorporated by reference into this Annual Report, and you should not consider information contained on our website as part of this Annual Report. You may access, free of charge, our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current
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Reports on Form 8-K, plus amendments to such reports as filed or furnished pursuant to Sections 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), through the “Investor Relations” portion of our website as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission (the “SEC”).
We have adopted a written Code of Ethics and Business Conduct Policy (the “Code of Conduct”) that applies to all of our employees and directors, including, but not limited to, our principal executive officer, principal financial officer and principal accounting officer or controller or persons performing similar functions. The Code of Conduct is available on the “Corporate Responsibility” portion of our website and our Corporate Governance Guidelines and the charters of the audit, compensation and nominating and corporate governance committees of our Board of Directors are available on the “Investor Relations” portion of our website. In the event we amend the Code of Conduct, or provide any waivers of the Code of Conduct to our directors or executive officers, we will disclose these events on our website as required by the regulations of the New York Stock Exchange (the “NYSE”) and applicable law.
In addition, paper copies of these documents may be obtained free of charge by writing us at the following address: 116 Huntington Avenue, Boston, Massachusetts 02116, Attention: Investor Relations; or by calling us at (617) 375-7500.

ITEM 1A.RISK FACTORS

Risks Related to Our Business Strategy

A significant decrease in leasing demand for our communications infrastructure would materially and adversely affect our business and operating results, and we cannot control that demand.
A significant reduction in leasing demand for our communications infrastructure would materially and adversely affect our business, results of operations or financial condition. Factors that may affect such demand include:
increased mergers, consolidations or exits that reduce the number of communications service providers or increased use of network sharing among governments or communications service providers;
the financial condition of communications service providers, including as a result of the COVID-19 pandemic;
zoning, environmental, health, tax or other government regulations or changes in the application and enforcement thereof;
governmental licensing of spectrum or restriction or revocation of our customers’ spectrum licenses;
a decrease in demand for wireless or colocation services, including due to general economic conditions, disruption in the financial and credit markets or global social, political or health crises, such as the material adverse effect of the COVID-19 pandemic on the global economy and markets;
the ability and willingness of wireless and cloud service providers to maintain or increase capital expenditures on network infrastructure;
delays or changes in the deployment of next generation wireless technologies; and
technological changes.
If our customers consolidate their operations, exit their businesses or share site infrastructure to a significant degree, our growth, revenue and ability to generate positive cash flows could be materially and adversely affected.
Significant consolidation among our customers could reduce demand for our communications infrastructure and may materially and adversely affect our growth and revenues. Certain combined companies have rationalized duplicative parts of their networks or modernized their networks, and these and other customers could determine not to renew, or attempt to cancel, avoid or limit leases or related payments with us. In the event a customer terminates its business or separately sells its spectrum, we may experience increased churn as a result. Our ongoing contractual revenues and our future results may be negatively impacted if a significant number of these leases are terminated or not renewed. For example, see our discussion of carrier consolidation-driven churn in our Asia-Pacific property segment and churn as a result of the T-Mobile MLA in our U.S. & Canada property segment in Item 7 of this Annual Report, under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Overview.”
In addition, extensive sharing of site infrastructure, roaming or resale arrangements among wireless service providers, including due to increases in advanced network technology such as 5G, as an alternative to leasing our communications sites, without compensation to us, may cause new lease activity to slow if carriers utilize shared equipment rather than deploy new equipment, or may result in the decommissioning of equipment on certain existing sites because portions of the customers’ networks may become redundant.
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A substantial portion of our revenue is derived from a small number of customers, and we are sensitive to adverse changes in the creditworthiness and financial strength of our customers.
A substantial portion of our total operating revenues is derived from a small number of customers. If any of these customers are unwilling or unable to perform their obligations under their agreements with us, our revenues, results of operations, financial condition and liquidity could be materially and adversely affected.
One or more of our customers, or their parent companies, may experience financial difficulties, file for bankruptcy or reduce or terminate operations as a result of a prolonged economic downturn, economic difficulties (including those from the imposition of taxes, fees, regulations or judicial interpretations of regulations, and any associated penalties or interest, which may be substantial) or otherwise. The ongoing COVID-19 pandemic could materially and adversely affect our customers through disruptions of, among other things, their ability to procure their equipment through their supply chains and their ability to maintain liquidity and deploy network capital, with potential decreases in consumer spending contributing to liquidity risks. Such financial difficulties could result in uncollectible accounts receivable and an impairment of our deferred rent asset, tower asset, network location intangible asset, tenant-related intangible asset or goodwill. The loss of significant customers, or the loss of all or a portion of our anticipated lease revenues from certain customers, could have a material adverse effect on our business, results of operations or financial condition.
Due to the long-term nature of our customer leases, we depend on the continued financial strength of our customers. Many communications service providers operate with substantial levels of debt. In our international operations, many of our customers are subsidiaries of global telecommunications companies. These subsidiaries may not have the explicit or implied financial support of their parent entities.
In addition, many of our customers and potential customers rely on capital raising activities to fund their operations and capital expenditures, which may be more difficult or expensive in the event of downturns in the economy or disruptions in the financial and credit markets, such as the current environment driven by the significant disruptions caused by factors such as the COVID-19 pandemic, inflation, rising interest rates and supply chain disruptions. If our customers or potential customers are unable to raise adequate capital to fund their business plans or face capital constraints, they may reduce their spending, file for bankruptcy or reduce or terminate operations, which could materially and adversely affect demand for our communications infrastructure and our services business.
In the ordinary course of our business, we do occasionally experience disputes with our customers, generally regarding the interpretation of terms in our leases. Historically, we have resolved these disputes in a manner that did not have a material adverse effect on us or our relationships with our customers. However, it is possible that such disputes could lead to a termination of our leases with those customers, a material adverse modification of the terms of those leases or a deterioration in our relationships with those customers that leads to a failure to obtain new business from them, any of which could have a material adverse effect on our business, results of operations or financial condition. If we are forced to resolve any of these disputes through litigation, our relationship with the applicable customer could be terminated or damaged, which could lead to decreased revenue or increased costs, resulting in a corresponding adverse effect on our business, results of operations or financial condition.
Increasing competition within our industry may materially and adversely affect our revenue.
Our industry is highly competitive and our customers have numerous alternatives in leasing communications infrastructure assets. Competition due to pricing or alternative contractual arrangements from peers could materially and adversely affect our lease rates. We may not be able to renew existing customer leases or enter into new customer leases, or if we are able to renew or enter into new leases, they may be at rates lower than our current rates or on less favorable terms than our current terms, resulting in an adverse impact on our results of operations and growth rate.
Our expansion initiatives involve a number of risks and uncertainties, including those related to integrating acquired or leased assets, that could adversely affect our operating results, disrupt our operations or expose us to additional risk.
As we continue to acquire and build communications sites and other communications infrastructure assets, including data center facilities and related assets, in our existing markets and expand into new markets, we are subject to a number of risks and uncertainties, including not meeting our return on investment criteria and financial objectives, increased costs, assumed liabilities and the diversion of managerial attention. Achieving the benefits of acquisition and platform expansion initiatives depends in part on timely and efficient integration of operations, telecommunications infrastructure assets and personnel. Integration may be difficult and unpredictable for many reasons, including, among other things, portfolios without requisite permits, differing systems, cultural differences, conflicting policies, procedures and operations. Additionally, temporary business closures, social distancing measures and the potential unavailability of key personnel or a significant number of our employees as a result of COVID-19 are difficult to predict, and may have a negative impact on the timely and efficient integration of operations, telecommunications infrastructure assets and personnel. Significant acquisition-related integration
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costs, including certain nonrecurring charges such as costs associated with onboarding employees, integrating information technology systems, acquiring permits and visiting, inspecting, engineering and upgrading tower sites or other communications infrastructure assets, could materially and adversely affect our results of operations in the period in which such charges are recorded or our cash flow in the period in which any related costs are actually paid. Some of our acquired portfolios have included sites that do not meet our structural specifications, including sites that may be overburdened. In these cases, beyond additional capital expenditures, general liability risks associated with such portfolios will exist until such time as those portfolios are upgraded or otherwise remedied. In addition, integration may significantly burden management and internal resources, including through the potential loss or unavailability of key personnel. Our international expansion initiatives are subject to additional risks, such as those described above, as well as our ability to comply with bribery and anti-corruption laws such as the Foreign Corrupt Practices Act (the “FCPA”) and similar local laws.
Moreover, we may fail to successfully integrate the assets we acquire or fail to utilize such assets to their full capacity. If we are not able to meet these integration challenges, we may not realize the benefits we expect from our acquired portfolios and businesses, and our business, financial condition and results of operations will be adversely affected.
For example, failure to successfully and efficiently integrate acquired assets from the Telxius Acquisition (the “Telxius Assets”) into our operations may adversely affect our business, financial condition and results of operations. Integrating acquired portfolios of the Telxius Assets may require significant resources, including increased attention from our management team. Further, the significant acquisition-related integration costs could materially and adversely affect our results of operations in the periods in which such charges are recorded or our cash flow in the periods in which any related costs are actually paid. The integration of the Telxius Assets, which includes approximately 31,000 international communications sites, into our operations continues to be a significant undertaking, and we anticipate that we will incur certain nonrecurring charges as a result. Additional integration challenges include:
transitioning all data related to the Telxius Assets, tenants and landlords to a common information technology system;
successfully transitioning the lease rent payment and the tenant billing and collection processes; and
maintaining our standards, controls, procedures and policies with respect to the Telxius Assets.
As a result of our acquisitions, we have a substantial amount of intangible assets and goodwill. In accordance with accounting principles generally accepted in the United States (“GAAP”), we are required to assess our goodwill and other intangible assets annually or more frequently in the event of circumstances indicating potential impairment to determine if they are impaired. If, as a result of the factors noted above, the testing performed indicates that an asset may not be recoverable or the carrying value exceeds the fair value, we would be required to record a non-cash impairment charge in the period the determination is made.
Our platform expansion initiatives may not be successful, or we may be required to record impairment charges for our goodwill or for other intangible assets, which could have a material adverse effect on our business, results of operations or financial condition, and could limit our continued investments in such platform expansion initiatives.
In addition, as we continue to invest in partnership opportunities to support our expansion initiatives, our partners may have business or economic goals that are inconsistent or conflict with ours, be in positions to take action contrary to our interests, policies or objectives, have competing interests in our, or other, markets that could create conflict of interest issues, withhold consents contrary to our requests or become unable or unwilling to fulfill their commitments, any of which could present governance challenges with multiple partners or expose us to additional liabilities or costs, including requiring us to assume and fulfill the obligations of that partnership or to execute buyouts of their interests.
Failure to successfully and efficiently integrate and operate acquired data center facilities and related assets, including those acquired through the CoreSite Acquisition (the “CoreSite Assets”), into our operations may adversely affect our business, operations and financial condition.
Integrating acquired data center facilities and related assets may require significant resources, including increased attention from our management team. Further, the significant acquisition-related integration costs could materially and adversely affect our results of operations in the periods in which such charges are recorded or our cash flow in the periods in which any related costs are actually paid. The integration of the CoreSite Assets, which includes over 20 data centers across eight United States metro areas, into our operations will be a significant undertaking, and we anticipate that we will incur certain nonrecurring charges as a result. Additional integration challenges include, but are not limited to:
retaining existing customers at the CoreSite Assets;
unexpected costs associated with successfully developing and expanding the CoreSite Assets;
failure to recruit or retain key personnel;
maintaining our standards, controls, procedures and policies with respect to the CoreSite Assets; and
successfully marketing space on the CoreSite Assets, which will depend on a variety of factors, including (i) the demand for data center space, (ii) Internet gateway facilities or other technology-related real estate, (iii) the presence of
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multiple network carriers and cloud operators in our facilities, (iv) the mix of products and services offered by us, (v) the overall mix of customers, (vi) the presence of key customers attracting business through vertical market ecosystems, (vii) each data center’s operating reliability and security and (viii) our ability to effectively market and sell our services.
Additionally, we may fail to successfully operate the data centers we acquire or fail to utilize such assets to their full capacity. We must safeguard our customers’ infrastructure and equipment located in our data centers and ensure our data centers remain operational at all times. Problems at one or more of our data centers, whether or not within our control, could result in service interruptions or significant infrastructure or equipment damage. These could result from numerous factors, including human error, equipment failure, physical, electronic and cyber security breaches, fire, earthquake, hurricane, flood, tornado and other natural disasters, extreme temperatures, water damage, fiber cuts, power loss, terrorist acts, sabotage and vandalism, global pandemics or health emergencies, such as the COVID-19 pandemic, and failure of business partners.
We have service level commitment obligations to certain customers. As a result, service interruptions or significant equipment damage in our data centers could result in difficulty maintaining service level commitments to these customers and potential claims related to such failures. Because our data centers are critical to many of our customers’ businesses, service interruptions or significant equipment damage in our data centers could also result in lost profits or other indirect or consequential damages to our customers. In addition, any loss of service, equipment damage or inability to meet our service level commitment obligations could reduce the confidence of our customers and could consequently impair our ability to obtain and retain customers, which would adversely affect both our ability to generate revenues and our operating results. Furthermore, we are dependent upon internet service providers, telecommunications carriers and utility providers, some of which have experienced significant system failures and outages in the past. Our customers may in the future experience difficulties due to system failures unrelated to our systems and offerings. If, for any reason, these providers fail to provide the required services, our business, financial condition and results of operations could be adversely impacted.
New technologies or changes in our or a customer’s business model could make our communications infrastructure leasing business less desirable and result in decreasing revenues and operating results.
The development and implementation of new technologies designed to enhance the efficiency of wireless networks or changes in a customer’s business model could reduce the need for tower-based wireless services, decrease demand for tower space or reduce previously obtainable lease rates. In addition, if the industry trends toward deploying increased capital to the development and implementation of new technologies, then customers may allocate less of their budgets to leasing space on our towers. Examples of these technologies include more spectrally efficient technologies, which could relieve a portion of our customers’ network capacity needs and, as a result, could reduce the demand for tower-based antenna space. Additionally, certain small cell complementary network technologies or satellite services could shift a portion of our customers’ network investments away from traditional tower-based networks, which may reduce the need for carriers to add more equipment at certain communications sites. Moreover, the emergence of alternative technologies could reduce the need for tower-based broadcast services transmission and reception. Further, a customer may decide to cease outsourcing tower infrastructure or otherwise change its business model, which would result in a decrease in our revenue and operating results. Similarly, our data center site infrastructure may become antiquated due to the development of new systems that deliver power to, or eliminate heat from, the servers and other customer equipment that we house or the development of new technology that requires levels of power and cooling density that our facilities are not designed to provide. Our failure to innovate in response to the development and implementation of these or other new technologies or changes in a customer’s business model could have a material adverse effect on the growth of our business, results of operations or financial condition. Conversely, we may invest significant capital in technologies, platform expansion initiatives or new additions to our core business that may not provide expected returns or profitability, which could divert management attention and have a material adverse effect on our operating results.
Competition for assets could adversely affect our ability to achieve our return on investment criteria.
We may experience increased competition for the acquisition of communications infrastructure assets or contracts to build new communications infrastructure assets for customers, which could make the acquisition of high-quality assets significantly more costly or prohibitive or cause us to lose contracts to build new sites. Some of our competitors are larger and may have greater financial resources than we do, while other competitors may apply less stringent investment criteria than we do. In addition, we may not anticipate increased competition entering a particular market or competing for the same assets. Higher prices for assets or the failure to add new assets to our portfolio could make it more difficult to achieve our anticipated returns on investment or future growth, which could materially and adversely affect our business, results of operations or financial condition.
In addition, some of our data center competitors have significant advantages over us, including greater name recognition, longer operating histories, lower operating costs, lower levels of leverage, pre-existing relationships with current or potential customers, greater financial, marketing and other resources, access to better networks and access to less expensive power. These advantages could allow our data center competitors to respond more quickly or effectively to strategic opportunities and as a
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result, we may lose existing or potential data center customers, incur costs to improve our properties or be forced to reduce our rental rates. These risks are compounded by the fact that a significant percentage of our data center customer leases expire every year.
Risks Related to Our Financial Performance or General Economic Conditions
Our leverage and debt service obligations may materially and adversely affect our ability to raise additional financing to fund capital expenditures, future growth and expansion initiatives and to satisfy our distribution requirements.
Our leverage and debt service obligations, including as a result of our recent CoreSite Acquisition and Telxius Acquisition, could have significant negative consequences to our business, results of operations or financial condition, including:
requiring the dedication of a substantial portion of our cash flow from operations to service our debt, thereby reducing the amount of our cash flow available for other purposes, including capital expenditures and REIT distributions;
impairing our ability to meet one or more of the financial ratio covenants contained in our debt agreements or to generate cash sufficient to pay interest or principal due under those agreements, which could result in an acceleration of some or all of our outstanding debt and the loss of the towers securing such debt if a default remains uncured;
limiting our ability to obtain additional debt or equity financing, thereby placing us at a possible competitive disadvantage to less leveraged competitors and competitors that may have better access to capital resources, including with respect to acquiring assets; and
limiting our flexibility in planning for, or reacting to, changes in our business and the markets in which we compete.
We may need to raise additional capital through debt financing activities, asset sales or equity issuances, even if the then-prevailing market conditions are not favorable, to fund capital expenditures, future growth and expansion initiatives, required purchases of our partners’ interests and to satisfy our distribution requirements and debt service obligations and leverage requirements, including financial ratio covenants. An increase in our total leverage could lead to a downgrade of our credit rating below investment grade, which could negatively impact our ability to access credit markets or preclude us from obtaining funds on investment grade terms, rates and conditions or subject us to additional loan covenants, which could accelerate our debt repayment obligations. Further, certain of our current debt instruments limit the amount of indebtedness we and our subsidiaries may incur. Additional financing, therefore, may be unavailable, more expensive or restricted by the terms of our outstanding indebtedness.
Further, market volatility and disruption caused by factors such as COVID-19, inflation, rising interest rates and supply chain disruptions may impact our ability to raise additional capital through debt and equity financing activities or our ability to repay or refinance maturing liabilities, or impact the terms of any new obligations, which in turn may have an adverse impact on our credit ratings. The extent to which these factors will impact our business and financial results will depend on future developments, which are highly uncertain and cannot be predicted at this time due to the rapid evolution of this uncertain situation.
Rising inflation may adversely affect us by increasing costs beyond what we can recover through price increases.
Inflation can adversely affect us by increasing the costs of land, materials, labor and other costs required to manage and grow our business. In addition, should inflation rates exceed our fixed escalator percentages in markets where our leases include fixed escalators, our returns could be adversely affected. In an inflationary environment, such as the current economic environment, depending on the terms of our contracts and other economic conditions, we may be unable to raise prices enough to keep up with the rate of inflation, which would reduce our profit margins and returns. If we are unable to increase our prices to offset the effects of inflation, our business, results of operations and financial condition could be materially and adversely affected.
In addition, inflation is often accompanied by higher interest rates. The impact of COVID-19 may increase uncertainty in the global financial markets, as well as the possibility of high inflation and extended economic downturn, which could reduce our ability to incur debt or access capital and impact our results of operations and financial condition even after these conditions improve.
Restrictive covenants in the agreements related to our securitization transactions, our credit facilities and our debt securities could materially and adversely affect our business by limiting flexibility, and we may be prohibited from paying dividends on our common stock, which may jeopardize our qualification for taxation as a REIT.
The agreements related to our securitization transactions include operating covenants and other restrictions customary for loans subject to rated securitizations. Among other things, the borrowers under the agreements are prohibited from incurring other indebtedness for borrowed money or further encumbering their assets. A failure to comply with the covenants in the agreements could prevent the borrowers from taking certain actions with respect to the secured assets and could prevent the borrowers from distributing any excess cash from the operation of such assets to us. If the borrowers were to default on any of the loans, the
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servicer on such loan could seek to foreclose upon or otherwise convert the ownership of the secured assets, in which case we could lose such assets and the cash flow associated with such assets.
The agreements for our credit facilities also contain restrictive covenants and leverage and other financial maintenance tests that could limit our ability to take various actions, including incurring additional debt, guaranteeing indebtedness or making distributions to stockholders, including our required REIT distributions, and engaging in various types of transactions, including mergers, acquisitions and sales of assets. Additionally, our credit facilities restrict our and our subsidiaries’ ability to incur liens securing our or their indebtedness. These covenants could have an adverse effect on our business by limiting our ability to take advantage of financing, new tower or other communications infrastructure development, mergers and acquisitions or other opportunities. Our credit agreements also contain cross-default and/or cross-acceleration provisions, which may be triggered if we default on certain indebtedness in excess of certain thresholds. In the event of such a default, the resulting cross-defaults or cross-accelerations could have an adverse effect on our business and financial condition. Further, reporting and information covenants in our credit agreements and indentures require that we provide financial and operating information within certain time periods. If we are unable to provide the required information on a timely basis, we would be in breach of these covenants. For more information regarding the covenants and requirements discussed above, please see Item 7 of this Annual Report under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources—Factors Affecting Sources of Liquidity” and note 8 to our consolidated financial statements included in this Annual Report.
We also enter into hedges for certain debt instruments, which may have an adverse impact on our results to the extent that the counterparties do not perform as expected at the inception of each hedge.
We may be adversely affected by changes in LIBOR reporting practices, the method in which LIBOR is determined or the use of alternative reference rates.
The United Kingdom’s Financial Conduct Authority (the “FCA”), which regulates the London Interbank Offered Rate (“LIBOR”), announced plans to phase out certain LIBOR rates by June 2023. As contemplated, the continuation of LIBOR on the current basis cannot be assured after June 2023, and LIBOR will cease to exist or otherwise be unsuitable for benchmarking. While our bank facilities contain fallback provisions to establish an alternative rate in the event LIBOR is unavailable, the elimination of LIBOR could have an adverse impact on our business, results of operations, or financial condition. Financial institutions may replace LIBOR with a new index calculated by short-term repurchase agreements, the Secured Overnight Financing Rate; however, no consensus exists as to what may become accepted alternatives to LIBOR, whether LIBOR rates will cease to be published or supported before June 2023 or whether any additional reforms to LIBOR may be enacted in the United Kingdom or elsewhere. Furthermore, the use of an alternative rate could result in increased costs, including increased interest expense, and increased borrowing and hedging costs in the future. We cannot predict the effect of the FCA’s decision not to sustain LIBOR or, if changes ultimately are made to LIBOR, the effect those changes may have on our interest expense related to borrowings under our bank facilities, certain other debt service obligations and interest swap agreements, which could potentially negatively impact our financial condition.
Risks Related to Laws and Regulations
Our business, and that of our customers, is subject to laws, regulations and administrative and judicial decisions, and changes thereto, that could restrict our ability to operate our business as we currently do or impact our competitive landscape.
Our business, and that of our customers, is subject to federal, state, local and foreign laws, treaties and regulations and administrative and judicial decisions. In certain jurisdictions, these regulations, laws and treaties could be applied or be enforced retroactively. Zoning authorities and community organizations are sometimes opposed to the construction of communications sites in their communities, which can delay, prevent or increase the cost of new tower construction, modifications, additions of new antennas to a site or site upgrades, thereby limiting our ability to respond to customer demands. Existing or new regulatory policies, regulations or laws may materially and adversely affect the timing, cost or completion of our communications sites or result in changes in the competitive landscape that may negatively affect our business. Noncompliance could result in the imposition of fines or an award of damages to litigants or result in decreased revenue. In addition, in certain jurisdictions, we and certain of our customers are required to pay annual license fees, which may be subject to substantial increases by the government, or new fees may be enacted and applied retroactively. Governmental licenses may also be subject to periodic renewal and additional conditions to receive or maintain such license. Additionally, we have government customers for several of our communications sites and data centers, which subjects us to risks including early termination, audits, investigations, sanctions and penalties.
In addition, federal, state and local governments in many of our markets have recently taken actions to contain the spread of COVID-19, including travel bans, quarantines, shelter-in-place orders and business shutdowns, among others, and may take
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additional actions in the future. In response to governmental actions, we have taken a variety of measures, including providing support for our customers remotely, supporting continued work-from-home arrangements and restricting travel for our employees where practicable and other modifications to our business practices. These governmental actions could remain effective for a prolonged period of time with potential material adverse impacts on our, and our customers’, business operations. Moreover, while the restrictions and limitations noted above may be relaxed or rolled back if and when COVID-19 abates or vaccinations become more prevalent, such government actions may be reinstated as the pandemic continues to evolve and in response to actual or potential resurgences, including due to emerging variants. The scope and timing of any such reinstatement is difficult to predict and may materially and adversely affect our operations in the future.
Furthermore, the tax laws, regulations, applicable license terms and conditions, and interpretations governing our business, and that of our customers, in jurisdictions where we operate, may change at any time, potentially with retroactive effect. This includes changes in tax laws, spectrum use terms, administrative compliance guidance or judicial interpretations thereof. For example, the definition and application of AGR in India and associated fees and charges may have a material financial impact on certain of our customers which could affect their ability to perform their obligations under agreements with us. Changes in laws, regulations and judicial decisions could have a more significant impact on us as a REIT relative to other REITs due to the nature of our business and our use of taxable REIT subsidiaries. These factors could materially and adversely affect our business, results of operations or financial condition.
Our foreign operations are subject to economic, political and other risks that could materially and adversely affect our revenues or financial position, including risks associated with fluctuations in foreign currency exchange rates.
Our international business operations and our potential expansion into additional new markets in the future expose us to potential adverse financial and operational problems not typically experienced in the United States. We anticipate that revenues from our international operations will continue to grow. Accordingly, our business is subject to risks associated with doing business internationally, including:
uncertain, inconsistent or changing laws, regulations, rulings or methodologies impacting our existing and anticipated international operations, fees or other requirements directed specifically at the ownership and operation of communications infrastructure or our international acquisitions, any of which laws, fees or requirements may be applied retroactively or with significant delay;
failure to retain our tax status or to obtain an expected tax status for which we have applied;
expropriation resulting in government takeover of customer operations or governmental regulation restricting foreign ownership or requiring reversion or divestiture;
laws or regulations that tax or otherwise restrict repatriation of earnings or other funds or otherwise limit distributions of capital;
changes in a specific country’s or region’s political or economic conditions, including inflation or currency devaluation;
changes to zoning regulations or construction laws, which could be applied retroactively to our existing communications infrastructure;
actions restricting or revoking our customers’ spectrum licenses, or alterations or interpretations thereof, or suspending or terminating business under prior licenses;
failure to comply with anti-bribery laws such as the FCPA or similar local anti-bribery laws, or the Office of Foreign Assets Control requirements;
failure to comply with data privacy laws or other protections of employee health and personal information;
material site issues related to security, fuel availability and reliability of electrical grids;
significant increases in, or implementation of new, license surcharges on our revenue;
loss of key personnel, including expatriates, in markets where talent is difficult or expensive to acquire; and
price-setting or other similar laws or regulations for the sharing of passive infrastructure.
We also face risks associated with changes in foreign currency exchange rates, including those arising from the impacts of COVID-19 on the global economy and markets and those arising from our operations, investments and financing transactions related to our international business. Volatility in foreign currency exchange rates, which has increased in the last few years as a result of uncertainties caused by COVID-19, can also affect our ability to plan, forecast and budget for our international operations and expansion efforts. Our revenues earned from our international operations are primarily denominated in their respective local currencies. We have not historically engaged in significant currency hedging activities relating to our non-U.S. Dollar operations, and a weakening of these foreign currencies against the U.S. Dollar would negatively impact our reported revenues, operating profits and income.
If we fail to remain qualified for taxation as a REIT, we will be subject to tax at corporate income tax rates, which may substantially reduce funds otherwise available, and even if we qualify for taxation as a REIT, we may face tax liabilities that impact earnings and available cash flow.
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Commencing with the taxable year beginning January 1, 2012, we have operated as a REIT for federal income tax purposes. Qualification for taxation as a REIT requires the application of certain highly technical and complex provisions of the Internal Revenue Code of 1986, as amended (the “Code”), which provisions may change from time to time, to our operations as well as various factual determinations concerning matters and circumstances not entirely within our control. Further, tax legislation may adversely affect our ability to remain qualified for taxation as a REIT or the benefits or desirability of remaining so qualified. There are few judicial or administrative interpretations of the relevant provisions of the Code.

If, in any taxable year, we fail to qualify for taxation as a REIT and are not entitled to relief under the Code:
we will not be allowed a deduction for distributions to stockholders and would be subject to federal and state income tax on our taxable income at regular corporate income tax rates, which could be substantial in amount, and may require us to borrow additional funds or liquidate some investments to pay any additional tax liability and, accordingly, may reduce funds available for other purposes; and
we will be disqualified from REIT tax treatment for the four taxable years immediately following the year during which we were so disqualified.
We are subject to certain federal, state, local and foreign taxes on our income and assets, including taxes on any undistributed income and state, local or foreign income, franchise, property and transfer taxes. While state and local income tax regimes often parallel the U.S. federal income tax regime for REITs, many of these jurisdictions differ in their treatment of REITs. For example, some state and local jurisdictions currently or in the future may limit or eliminate a REIT’s deduction for dividends paid, which could increase our income tax expense. We are also subject to the continual examination of our income tax returns by the U.S. Internal Revenue Service and state, local and foreign tax authorities. The results of an audit and examination of previously filed tax returns and continuing assessments of our tax exposures may have an adverse effect on our provision for income taxes and cash tax liability.
Furthermore, we have owned and may from time to time own direct and indirect ownership interests in subsidiary REITs, which must also comply with the same REIT requirements that we must satisfy, together with all other rules applicable to REITs. If the subsidiary REIT is determined to have failed to qualify for taxation as a REIT and certain relief provisions do not apply, then the subsidiary REIT would be subject to federal income tax, which tax we would economically bear along with applicable penalties and interest. In addition, our ownership of shares in such subsidiary REIT would fail to be a qualifying asset for purposes of the asset tests applicable to REITs and any dividend income or gains derived by us from such subsidiary REIT may cease to be treated as income that qualifies for purposes of the 75% gross income test. These consequences could have a material adverse effect on our ability to comply with the REIT income and asset tests, and thus our ability to qualify for taxation as a REIT.
Complying with REIT requirements may limit our flexibility or cause us to forego otherwise attractive opportunities.
Our use of TRSs enables us to engage in non-REIT qualifying business activities. Under the Code, no more than 20% of the value of the assets of a REIT may be represented by securities of one or more TRSs and no more than 25% of the value of the assets of the REIT may be represented by non-qualifying assets (including securities of one or more TRSs). This limitation may hinder our ability to make certain attractive investments or take advantage of acquisition opportunities, including the purchase of non-qualifying assets, the expansion of non-real estate activities and investments in the businesses to be conducted by our TRSs, and to that extent limit our opportunities and our flexibility to change our business strategy.
Further, as a REIT, we must distribute to our stockholders an amount equal to at least 90% of our REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain). To meet our annual distribution requirements, we may be required to distribute amounts that may otherwise be used for our operations, including amounts that may otherwise be invested in future acquisitions, capital expenditures or repayment of debt. As no more than 25% of our gross income may consist of dividend income from our TRSs and other non-qualifying types of income, our ability to receive distributions from our TRSs may be limited, which may impact our ability to fund distributions to our stockholders or to use income of our TRSs to fund other investments.
In addition, the majority of our income and cash flows from our TRSs are generated from our international operations. In many cases, there are local withholding taxes and currency controls that may impact our ability or willingness to repatriate funds to the United States to help satisfy REIT distribution requirements.
We could have liability under environmental and occupational safety and health laws.
Our operations are subject to various federal, state, local and foreign environmental and occupational safety and health laws and regulations, including those relating to the management, use, storage, disposal, emission and remediation of, and exposure to, hazardous and non-hazardous substances, materials and wastes. As the owner, lessee or operator of real property and facilities, including generators, we may be liable for substantial costs of investigation, removal or remediation of soil and groundwater
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contaminated by hazardous materials, and for damages and costs relating to off-site migration of hazardous materials, without regard to whether we, as the owner, lessee or operator, knew of, or were responsible for, the contamination. We may also be liable for certain costs of remediating contamination at third-party sites to which we sent waste for disposal, even if the original disposal may have complied with all legal requirements at the time. Many of these laws and regulations contain information reporting and record keeping requirements. We may not be at all times in compliance with all environmental requirements. Further, our data center properties are subject to various federal, state and local regulations, such as state and local fire and life safety regulations and ADA federal requirements. We may be subject to potentially significant fines or penalties if we fail to comply with any of these requirements.
The requirements of the environmental and occupational safety and health laws and regulations are complex, change frequently and could become more stringent in the future. In certain jurisdictions, these laws and regulations could be applied retroactively or be broadened to cover situations or persons not currently considered. It is possible that these requirements will change or that liabilities will arise in the future in a manner that could have a material adverse effect on our business, results of operations or financial condition. While we maintain environmental and workers’ compensation insurance, we may not have adequate insurance to cover all costs, fines or penalties.
Risks Related to the Operation of Our Business
Our towers, fiber networks, data centers or computer systems may be affected by natural disasters (including as a result of climate change) and other unforeseen events for which our insurance may not provide adequate coverage or result in increased insurance premiums.
Our towers, fiber networks, data centers and computer systems are subject to risks associated with natural disasters, such as hurricanes, ice and windstorms, tornadoes, floods, earthquakes and wildfires, as well as other unforeseen events, such as the potential adverse effects of COVID-19 or other pandemics and acts of terrorism. During the past several years, we have seen an increase in severe weather events and expect this trend to continue due to climate change. Climate change or efforts to regulate emissions may also have direct or indirect effects on our business by increasing the cost of emission compliance or fuel we need to deliver primary power to our customers under our contractual obligations, typically through diesel-powered generators, in emerging markets. Additional environmental liabilities, such as contamination, asbestos-containing building materials and mold or other air quality issues at some of our data centers, could arise and have a material adverse effect on our financial condition and performance.
In addition, governmental initiatives to address climate change and future initiatives could, if adopted, require us and our customers to make capital expenditures to be compliant with these initiatives and increase our and our customers’ costs. Failure to comply with applicable laws and regulations or other requirements imposed on us could also lead to fines and/or lost revenue. We could also face a negative impact on our reputation with the public and our customers if we violate climate change laws or regulations. In October 2021, we adopted science-based targets, which were approved by the Science Based Targets initiative and are in line with the goals set forth in the 2015 Paris Agreement. These goals may require us to expend significant resources to meet them, which could increase our operational costs. Failing to meet these goals could result in customer dissatisfaction and damage to our reputation with our key stakeholders, which could in turn adversely impact our results of operations.
Further, any damage or destruction to, or inability to access, our towers, fiber networks, data centers or computer systems, as a result of measures implemented in response to COVID-19 or otherwise, may cause supply chain delays or impact our ability to provide services to our customers and lead to customer loss, which could have a material adverse effect on our business, results of operations or financial condition and also, our communications sites could be subject to attacks instigated by claims that the deployment of 5G networks is linked to adverse health effects.
While we maintain insurance coverage for certain natural disasters and business interruption, we may not have adequate insurance to cover the associated costs of repair or reconstruction of sites or fiber for a major future event, lost revenue, including from new customers that could have been added to our towers, fiber networks or data centers but for the event, or other costs to remediate the impact of a significant event, such was wildfire damage caused by our towers. Further, we may be liable for damage caused by towers that collapse for any number of reasons including structural deficiencies, which could harm our reputation and require us to incur costs for which we may not have adequate insurance coverage.
If we, or third parties on which we rely, experience technology failures, including cybersecurity incidents or the loss of personally identifiable information, we may incur substantial costs and suffer other negative consequences, which may include reputational damage.
As part of our normal business activities, including in our data centers, we rely on energy systems, communication networks, information technology and other computing resources. We may be vulnerable to physical or cybersecurity breaches that could disrupt our operations and have a material adverse effect on our financial performance and operating results. We face risks
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associated with unauthorized access to our or our vendors’ computer systems, loss or destruction of data, computer viruses, malware, distributed denial-of-service attacks or other malicious activities. These threats may result from human error, equipment failure or fraud or malice on the part of employees or third parties. A party who is able to compromise the security measures on our or our vendors’ networks or the security of our communications infrastructure could misappropriate either our proprietary information or the personal information of our customers or our employees, or cause interruptions or malfunctions in our operations or our customers’ operations. As we provide assurances to our customers that we provide a high level of security, such a compromise could be particularly harmful to our brand and reputation. We may be required to expend significant capital and resources to protect against such threats or to alleviate problems caused by breaches in security.
Globally, the frequency, severity and sophistication of cybersecurity incidents have increased, and these trends may continue. We are continuously evaluating and enhancing our cybersecurity and information security systems and creating new systems and processes. However, there can be no assurance that these measures will be effective in preventing or limiting the impact of future cybersecurity incidents. As techniques used to breach security grow in frequency and sophistication, and are generally not recognized until launched against a target, we, or our vendors, may not be able to promptly detect that a cyber breach has occurred or implement security measures in a timely manner. If and when implemented, we, or our vendors, may not be able to determine the extent to which these measures could be circumvented. Any breaches that may occur could expose us to increased risk of lawsuits, regulatory penalties, loss of existing or potential customers, damage relating to loss of proprietary information, harm to our reputation and increases in our security costs, which could have a material adverse effect on our financial performance and operating results. We offer managed services in certain of our data centers where we provide “smart hands” services for our customers. The access to our customers’ networks and data, which is gained from these services, creates some risk that our customers’ networks or data will be improperly accessed. If we were held responsible for any such breach, it could result in a significant loss to us, including damage to our customer relationships, harm to our brand and reputation and legal liability. Additionally, while we maintain insurance coverage for cybersecurity incidents, we may not have adequate insurance to cover the associated costs in the event of a breach resulting in loss of data, such as personally identifiable information or other such data protected by data privacy or other laws, and we may be liable for damages, fines and penalties for such losses under applicable regulatory frameworks.
Although we and our vendors have disaster recovery programs and security measures in place, if our computer systems and our backup systems are compromised, degraded, damaged, breached or otherwise cease to function properly, we could suffer interruptions in our operations, including our ability to correctly record, process and report financial information, our customers’ network availability may be impacted or we could unintentionally allow misappropriation of proprietary or confidential information (including information about our customers or landlords, or customer information on our fiber, data center or managed networks businesses), which could result in a loss of revenue, damage to our reputation, damage to our customer and vendor relationships, litigation, regulatory investigations and penalties under existing or future data privacy laws and require us to incur significant costs to remediate or otherwise resolve these issues. In addition, our recent acquisitions, including our acquisitions of data centers, may increase our exposure to the risks described above and have material and adverse effects on our business.
Our costs could increase and our revenues could decrease due to perceived health risks from radio emissions, especially if these perceived risks are substantiated.
Public perception of possible health risks associated with cellular and other wireless communications technology could slow the growth of wireless companies, which could in turn slow our growth. In particular, negative public perception of, and regulations regarding, these perceived health risks, including claims that the deployment of 5G networks is linked to adverse health effects, could undermine the market acceptance of wireless communications services and increase opposition to the development and expansion of tower sites. If a scientific study, court decision or government agency ruling resulted in a finding that radio frequency emissions pose health risks to consumers, it could negatively impact our customers and the market for wireless services, which could materially and adversely affect our business, results of operations or financial condition. We do not maintain any significant insurance with respect to these matters.
If we are unable to protect our rights to the land under our towers and buildings in which our data centers are located, it could adversely affect our business and operating results.
Our real property interests relating to our towers consist primarily of leasehold and sub-leasehold interests, fee interests, easements, licenses and rights-of-way. A loss of these interests at a particular tower site may interfere with our ability to operate that tower site and generate revenues. For various reasons, we may not always have the ability to access, analyze and verify all information regarding titles and other issues prior to completing an acquisition of communications sites, which can affect our rights to access and operate a site. From time to time, we also experience disputes with landowners regarding the terms of easements or ground agreements for land under towers, which can affect our ability to access and operate tower sites. Further, for various reasons, landowners may not want to renew their ground agreements with us, they may lose their rights to the land, or they may transfer their land interests to third parties, including ground lease aggregators, which could affect our ability to
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renew ground agreements on commercially viable terms. A significant number of the communications sites in our portfolio are located on land we lease pursuant to long-term operating leases. Further, for various reasons, title to property interests in some of the foreign jurisdictions in which we operate may not be as certain as title to our property interests in the United States. Our inability to protect our rights to the land under our towers may have a material adverse effect on our business, results of operations or financial condition.
We do not own the buildings for all of our data centers and our business could be harmed if we are unable to renew the leases for these data centers at favorable terms or at all, though we generally have the right to extend the terms of our leases when the primary terms of the leases expire. Failure to increase operating revenues to sufficiently offset any potential increase in lease costs, including as a result of the current inflationary environment, would adversely impact our operating income. We could also lose customers due to the disruptions in their operations caused by our inability to renew our data center leases. Additionally, we rely on our landlords for basic maintenance of our leased data centers. If such landlords have not maintained our leased properties sufficiently, we may be forced into an early exit from one or more of these data centers, which could be disruptive to our business.
If we are unable or choose not to exercise our rights to purchase towers that are subject to lease and sublease agreements at the end of the applicable period, our cash flows derived from those towers will be eliminated.
Our communications real estate portfolio includes towers that we operate pursuant to lease and sublease agreements that include a purchase option at the end of the lease period. We may not have the required available capital to exercise our right to purchase the towers at the end of the applicable period, or we may choose, for business or other reasons, not to do so. If we do not exercise these purchase rights, and are unable to extend the lease or sublease or otherwise acquire an interest that would allow us to continue to operate these towers after the applicable period, we will lose the cash flows derived from the towers.

ITEM 1B.UNRESOLVED STAFF COMMENTS
None. 

ITEM 2.PROPERTIES
As of December 31, 2021, we owned and operated a portfolio of 220,131 communications sites, including 1,778 DAS networks. See the table in Item 7 of this Annual Report, under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Overview” for more detailed information on the geographic locations of our communications sites. In addition, we own property interests that we lease to communications service providers and third-party tower operators in Canada and the United States, which are included in our U.S. & Canada property segment, and in Australia, which are included in our Asia-Pacific property segment, and also own and operate data center facilities and related assets in the United States, which are included in our Data Centers segment.
Our interests in our communications sites consist of a variety of ownership interests, including leases created by long-term ground lease agreements, easements, licenses or rights-of-way granted by government entities.
A typical tower site consists of a compound enclosing the tower site, a tower structure and, in some cases, one or more equipment shelters that house a variety of transmitting, receiving and switching equipment. In addition, many of our international sites typically include power generators and batteries, which are often used for primary power in lieu of an electric grid connection in select markets. The principal types of our towers are guyed, self-supporting lattice and monopole, and rooftop towers in our international markets.
A guyed tower includes a series of cables attaching separate levels of the tower to anchor foundations in the ground and can reach heights of up to 2,000 feet. A typical guyed broadcast tower can be located a tract of land of up to 20 acres.
A self-supporting lattice tower typically tapers from the bottom up and usually has three or four legs. A lattice tower can reach heights of up to 1,000 feet, although most lattice structures are between 200 and 400 feet. Depending on the height of the tower, a lattice tower site can be located on a tract of land of 10,000 square feet for a rural site or fewer than 2,500 square feet for a metropolitan site.
A monopole tower is a tubular structure that is used primarily to address space constraints or aesthetic concerns. Monopoles typically have heights ranging from 50 to 200 feet. A monopole tower site used in metropolitan areas for a typical wireless communications tower can be located on a tract of land of fewer than 2,500 square feet.
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Rooftop towers are primarily used in metropolitan areas in our Asia-Pacific, Africa, Europe and Latin America markets, where locations for traditional tower structures are unavailable. Rooftop towers typically have heights ranging from 10 to 100 feet.
U.S. & Canada Property Segment Encumbered Sites. As of December 31, 2021, the loan underlying the securitization transactions completed in March 2013 and March 2018 (the “2013 Securitization” and the “2018 Securitization”, respectively, and together, the “Trust Securitizations”) is secured by mortgages, deeds of trust and deeds to secure the loan on substantially all of the 5,113 broadcast and wireless communications towers and related assets owned by the borrowers (the “Trust Sites”) and the secured revenue notes issued in a private transaction completed in May 2015 (the “2015 Securitization”) are secured by mortgages, deeds of trust and deeds to secure debt on substantially all of the 3,531 communications sites owned by subsidiaries of the issuer (the “2015 Secured Sites”).
There are no encumbered sites in our Asia-Pacific, Africa, Europe or Latin America property segments or in our Data Centers segment.
Ground Leases. Of the 218,353 towers in our portfolio as of December 31, 2021, approximately 90% were located on land we lease. Typically, we seek to enter long-term ground leases, which have initial terms of approximately five to ten years with one or more automatic or exercisable renewal periods. As a result, 41% of the ground leases for our sites have a final expiration date of 2031 and beyond.
Customers. Our customers are primarily wireless service providers, broadcasters and other companies in a variety of industries. For the year ended December 31, 2021, our top three customers by total revenue were T-Mobile (20%), AT&T (19%) and Verizon Wireless (13%).
Across most of our markets, our tenant leases for our communications sites with wireless carriers have initial non-cancellable terms of five to ten years with multiple renewal terms. As a result, approximately 64% of our current tenant leases have a renewal date of 2027 or beyond.
Data Centers. We own and operate data center facilities and related assets, and as of December 31, 2021, our data center portfolio consisted of 27 data center facilities across ten United States markets, including the assets acquired as part of the CoreSite Acquisition, as well as our previously acquired data center facilities, across 3.1 million net rentable square feet (“NRSF”).
Offices. Our principal corporate headquarters is leased and located in Boston, Massachusetts, where we currently lease approximately 40,000 square feet of office space. We also own or have entered into long-term leases for the majority of our facilities in international and regional locations for the management and operation of our property and services businesses, including offices in each of our U.S. & Canada, Asia-Pacific, Africa, Europe, Latin America and Data Centers segments. Our international headquarters is leased and located in Amsterdam, Netherlands. We believe that our owned and leased facilities are suitable and adequate to meet our anticipated needs.

ITEM 3.LEGAL PROCEEDINGS
We periodically become involved in various claims and lawsuits that are incidental to our business. In the opinion of management, after consultation with counsel, there are no matters currently pending that would, in the event of an adverse outcome, have a material impact on our consolidated financial position, results of operations or liquidity.

ITEM 4.MINE SAFETY DISCLOSURES
N/A.
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PART II
ITEM 5.MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES
Our common stock is listed on the NYSE under the ticker symbol AMT. As of February 17, 2022, we had 455,884,806 outstanding shares of common stock and 141 registered holders.
Dividends
As a REIT, we must annually distribute to our stockholders an amount equal to at least 90% of our REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain). Generally, we have distributed and expect to continue to distribute all or substantially all of our REIT taxable income after taking into consideration our utilization of net operating losses (NOLs).
The amount, timing and frequency of future distributions will be at the sole discretion of our Board of Directors and will depend upon various factors, a number of which may be beyond our control, including our financial condition and operating cash flows, the amount required to maintain our qualification for taxation as a REIT and reduce any income and excise taxes that we otherwise would be required to pay, limitations on distributions in our existing and future debt and preferred equity instruments, our ability to utilize NOLs to offset our distribution requirements, limitations on our ability to fund distributions using cash generated through our TRSs and other factors that our Board of Directors may deem relevant.
Performance Graph
This performance graph is furnished and shall not be deemed ‘‘filed’’ with the SEC or subject to Section 18 of the Exchange Act, nor shall it be deemed incorporated by reference in any of our filings under the Securities Act of 1933, as amended.
The following graph compares the cumulative total stockholder return on our common stock with the cumulative total return of the S&P 500 Index, the Dow Jones U.S. Telecommunications Equipment Index and the FTSE Nareit All Equity REITs Index. The performance graph assumes that on December 31, 2016, $100 was invested in each of our common stock, the S&P 500 Index, the Dow Jones U.S. Telecommunications Equipment Index and the FTSE Nareit All Equity REITs Index. The cumulative return shown in the graph assumes reinvestment of all dividends. The performance of our common stock reflected below is not necessarily indicative of future performance.
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 Cumulative Total Returns
 12/1612/1712/1812/1912/2012/21
American Tower Corporation$100.00 $137.69 $156.03 $230.69 $229.60 $305.10 
S&P 500 Index100.00 121.83 116.49 153.17 181.35 233.41 
Dow Jones U.S. Telecommunications Equipment Index100.00 123.05 133.55 155.24 158.83 231.68 
FTSE Nareit All Equity REITs Index100.00 108.67 104.28 134.17 127.30 179.87 
ITEM 6.[RESERVED]
N/A.

ITEM 7.MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
The discussion and analysis of our financial condition and results of operations that follow are based upon our consolidated financial statements, which have been prepared in accordance with GAAP. The preparation of our financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses and the related disclosure of contingent assets and liabilities at the date of our financial statements. Actual results may differ from these estimates and such differences could be material to the financial statements. This discussion should be read in conjunction with our consolidated financial statements included in this Annual Report and the accompanying notes, and the information set forth under the caption “Critical Accounting Policies and Estimates” below.
During the fourth quarter of 2021, as a result of the CoreSite Acquisition, we updated our reportable segments to add a Data Centers segment. The Data Centers segment is included within our property operations. We will now report our results in seven segments – U.S. & Canada property (which includes all assets in the United States and Canada, other than our data center facilities and related assets), Asia-Pacific property, Africa property, Europe property, Latin America property, Data Centers and Services. We believe this change provides greater visibility into our operating segments and aligns our reporting with management’s current approach of allocating costs and resources, managing growth and profitability and assessing the operating performance of our business segments. This change applies to our business operations results beginning with the fourth quarter of 2021 and had no impact on our consolidated financial statements for any prior periods. Historical financial information included in this Annual Report has not been adjusted as the amounts attributable to data center assets were insignificant as prior to to the fourth quarter of 2021, we owned one data center.    
In evaluating financial performance in each business segment, management uses, among other factors, segment gross margin and segment operating profit (see note 21 to our consolidated financial statements included in this Annual Report).
Executive Overview
We are one of the largest global REITs and a leading independent owner, operator and developer of multitenant communications real estate. Our primary business is the leasing of space on communications sites to wireless service providers, radio and television broadcast companies, wireless data providers, government agencies and municipalities and tenants in a number of other industries. In addition to the communications sites in our portfolio, we manage rooftop and tower sites for property owners under various contractual arrangements. We also hold other telecommunications infrastructure, fiber and property interests that we lease primarily to communications service providers and third-party tower operators, and, as discussed further below, we hold a portfolio of highly interconnected data center facilities and related assets in the United States. Our customers include our tenants, licensees and other payers. We refer to the business encompassing the above as our property operations, which accounted for 97% of our total revenues for the year ended December 31, 2021 and includes our U.S. & Canada property, Asia-Pacific property, Africa property, Europe property and Latin America property segments and Data Centers segment.
We also offer tower-related services in the United States, including site application, zoning and permitting and structural analysis, which primarily support our site leasing business, including the addition of new tenants and equipment on our sites.
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The following table details the number of communications sites, excluding managed sites, that we owned or operated as of December 31, 2021:  
Number of
Owned Towers
Number of
Operated 
Towers (1)
Number of
Owned DAS Sites
U.S. & Canada:
Canada218 — — 
United States27,276 15,363 451 
U.S. & Canada total27,494 15,363 451 
Asia-Pacific: (2)
Bangladesh120 — — 
India74,596 — 912 
Philippines97 — — 
Asia-Pacific total74,813 — 912 
Africa:
Burkina Faso707 — — 
Ghana3,384 661 28 
Kenya2,997 — 
Niger754 — — 
Nigeria6,980 — — 
South Africa2,923 — — 
Uganda3,710 — 12 
Africa total21,455 661 49 
Europe:
France3,444 310 
Germany14,739 — — 
Poland 49 — — 
Spain11,490 — — 
Europe total29,722 310 
Latin America:
Argentina487 — 11 
Brazil20,732 2,083 109 
Chile3,737 — 137 
Colombia4,982 — 
Costa Rica690 — 
Mexico9,845 186 92 
Paraguay1,443 — — 
Peru3,900 450 — 
Latin America total45,816 2,719 357 
_______________
(1)Approximately 95% of the operated towers are held pursuant to long-term finance leases, including those subject to purchase options.
(2)We also control land under carrier or other third-party communications sites in Australia, which provides recurring cash flow through tenant leasing arrangements.
In January 2021, we entered into the Telxius Acquisition, pursuant to which we agreed to acquire Telxius’ European and Latin American tower divisions, comprising approximately 31,000 communications sites in Argentina, Brazil, Chile, Germany, Peru and Spain, for approximately 7.7 billion EUR (approximately $9.4 billion at the date of signing), subject to certain adjustments. We completed the acquisition of nearly 27,000 communications sites in June 2021 and acquired the approximately 4,000 remaining communications sites in Germany in August 2021, for total consideration of approximately 7.9 billion EUR (approximately $9.6 billion as of the closing dates), subject to certain post-closing adjustments.
In December 2021, we completed the CoreSite Acquisition, through which we acquired over 20 data center facilities and related assets in eight United States markets, for total consideration of $10.4 billion, including the assumption and repayment of CoreSite’s existing debt.
As of December 31, 2021, our property portfolio included 27 operating data center facilities across ten markets in the United States that collectively comprise approximately 3.1 million NRSF of data center space, as detailed below:
Number of
Data Centers
Total NRSF (1)
(in thousands)
San Francisco Bay, CA940 
Los Angeles, CA686 
Northern Virginia, VA536 
New York, NY203 
Chicago, IL233 
Boston, MA143 
Denver, CO35 
Miami, FL30 
Orlando, FL129 
Atlanta, GA128 
Total27 3,063 
_______________
(1)Excludes approximately 0.4 million of office and light-industrial NRSF acquired as part of the CoreSite Acquisition.
In most of our markets, our tenant leases for our communications sites with wireless carriers generally have initial non-cancellable terms of five to ten years with multiple renewal terms. Accordingly, the vast majority of the revenue generated by our property operations during the year ended December 31, 2021 was recurring revenue that we should continue to receive in future periods. Most of our tenant leases for our communications sites have provisions that periodically increase the rent due under the lease, typically based on an annual fixed escalation (averaging approximately 3% in the United States) or an inflationary index in most of our international markets, or a combination of both. In addition, certain of our tenant leases provide for additional revenue primarily to cover costs, such as ground rent or power and fuel costs.
Based upon existing customer leases and foreign currency exchange rates as of December 31, 2021, we expect to generate over $61 billion of non-cancellable customer lease revenue over future periods, before the impact of straight-line lease accounting.
The revenues generated by our property operations may be affected by cancellations of existing tenant leases. As discussed above, most of our tenant leases with wireless carriers and broadcasters are multiyear contracts, which typically are non-cancellable; however, in some instances, a lease may be cancelled upon the payment of a termination fee.
Revenue lost from either tenant lease cancellations or the non-renewal of leases or rent renegotiations, which we refer to as churn, has historically not had a material adverse effect on the revenues generated by our consolidated property operations. During the year ended December 31, 2021, churn was approximately 4% of our tenant billings.
Beginning in late 2017, we experienced an increase in revenue lost from cancellations or non-renewals primarily due to carrier consolidation-driven churn in India, which compressed our gross margin and operating profit, particularly in our Asia-Pacific property segment, although this impact was partially offset by lower expenses due to reduced tenancy on existing sites and the decommissioning of certain sites. For the year ended December 31, 2021, aggregate carrier consolidation in India did not have a material impact on our consolidated property revenue, gross margin or operating profit, although overall churn rates in India remained elevated relative to historical levels.
We anticipate that our churn rate in India will moderate over time and result in reduced impacts on our property revenue, gross margin and operating profit. In the immediate term, we believe that our churn rate may remain elevated as our tenants in India evaluate how best to comply with the recent court rulings by the Supreme Court of India and determine their obligations under payment plans for the AGR fees and charges prescribed by such court, as further discussed in Item 1A of this Annual Report under the caption “Risk Factors—Our business, and that of our customers, is subject to laws, regulations and administrative and judicial decisions, and changes thereto, that could restrict our ability to operate our business as we currently do or impact our competitive landscape.” We expect to periodically evaluate the carrying value of our Indian assets, which may result in the realization of additional impairment expense or other similar charges. For more information, please see the information under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates.”
Additionally, we expect that our churn rate in our U.S. & Canada property segment will remain elevated for a period of several years due to contractual lease cancellations and non-renewals by T-Mobile, including legacy Sprint Corporation leases, pursuant to the terms of the T-Mobile MLA entered into in September 2020.
As further set forth in Item 1A of this Annual Report under the caption “Risk Factors,” the ongoing COVID-19 pandemic, as well as the response to mitigate its spread and effects, may adversely impact us and our customers and the demand for our communications infrastructure in the United States and globally. We have taken a variety of actions to ensure the continued availability of our communications infrastructure assets, while ensuring the safety and security of our employees, customers,
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vendors and surrounding communities. These measures include providing support for our customers remotely, supporting continued work-from-home arrangements and restricting travel for our employees where practicable and other modifications to our business practices. We will continue to actively monitor the situation and may take further actions as may be required by governmental authorities or that we determine are in the best interests of our employees, customers and business partners.
Property Operations Revenue Growth. Due to our diversified communications site portfolio, our tenant lease rates vary considerably depending upon numerous factors, including, but not limited to, amount, type and position of tenant equipment on the tower, remaining tower capacity and tower location. We measure the remaining tower capacity by assessing several factors, including tower height, tower type, environmental conditions, existing equipment on the tower and zoning and permitting regulations in effect in the jurisdiction where the tower is located. In many instances, tower capacity can be increased with relatively modest tower augmentation capital expenditures, which are often reimbursed to us.
The primary factors affecting the revenue growth of our property segments are:
Growth in tenant billings, including:
New revenue attributable to leasing additional space on our sites (“colocations”) and lease amendments;
Contractual rent escalations on existing tenant leases, net of churn; and
New revenue attributable to leases in place on day one on sites acquired or constructed since the beginning of the prior-year period.
Revenue growth from our Data Centers segment in the United States, including growth attributable to increased customer demand for space, power and interconnection services and solutions.
Revenue growth from other items, including additional tenant payments primarily to cover costs, such as ground rent or power and fuel costs included in certain tenant leases (“pass-through”), straight-line revenue and decommissioning.
We continue to believe that our site leasing revenue, which makes up the vast majority of our property segment revenue, is likely to increase due to the growing use of wireless services globally and our ability to meet the corresponding incremental demand for our communications real estate. By adding new tenants and new equipment for existing tenants on our sites, we are able to increase these sites’ utilization and profitability. We believe the majority of our site leasing activity will continue to come from wireless service providers, with tenants in a number of other industries contributing incremental leasing demand. Our site portfolio and our established tenant base provide us with new business opportunities, which have historically resulted in consistent and predictable organic revenue growth as wireless carriers seek to increase the coverage and capacity of their existing networks, while also deploying next generation wireless technologies. In addition, we intend to continue to supplement our organic growth by selectively developing or acquiring new sites in our existing and new markets where we can achieve our risk-adjusted return on investment objectives. 
Property Operations Organic Revenue Growth. Consistent with our strategy to increase the utilization and return on investment from our sites, our objective is to add new tenants and new equipment for existing tenants through colocation and lease amendments. Our ability to lease additional space on our sites is primarily a function of the rate at which wireless carriers and other tenants deploy capital to improve and expand their wireless networks. This rate, in turn, is influenced by the growth of wireless services, the penetration of advanced wireless devices, the level of emphasis on network quality and capacity in carrier competition, the financial performance of our tenants and their access to capital and general economic conditions. According to industry data, recent aggregate annual wireless capital spending in the United States has averaged at least $30 billion, resulting in consistent demand for our sites.
Based on industry research and projections, we expect that a number of key industry trends will result in incremental revenue opportunities for us:
In less advanced wireless markets where network deployments are in earlier stages, we expect these deployments to drive demand for our tower space as carriers seek to expand their footprints and increase the scope and density of their networks. We have established operations in many of these markets at the early stages of wireless development, which we believe will enable us to meaningfully participate in these deployments over the long term.
Subscribers’ use of mobile data continues to grow rapidly given increasing smartphone and other advanced device penetration, the proliferation of bandwidth-intensive applications on these devices and the continuing evolution of the mobile ecosystem. We believe carriers will be compelled to deploy additional equipment on existing networks while also rolling out more advanced wireless networks to address coverage and capacity needs resulting from this increasing mobile data usage.
The deployment of advanced mobile technology, such as 4G and 5G, will provide higher speed data services and further enable fixed broadband substitution. As a result, we expect that our tenants will continue deploying additional equipment across their existing networks.
Wireless service providers compete based on the quality of their networks, which is driven by capacity and coverage. To maintain or improve their network performance as overall network usage increases, our tenants continue to deploy
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additional equipment across their existing sites while also adding new cell sites. We anticipate increasing network densification over the next several years, as existing network density is anticipated to be insufficient to account for rapidly increasing levels of wireless data usage.
Wireless service providers continue to acquire additional spectrum, and as a result are expected to add additional sites and equipment to their networks as they seek to optimize their network configuration and utilize additional spectrum. We expect this to be particularly relevant in the context of higher-band spectrum such as 2.5 gigahertz (GHz) and C-Band being deployed for 5G, as these spectrum assets tend to have more limited propagation characteristics compared to the lower-band spectrum that has historically been deployed on our towers.
Next generation technologies requiring wireless connectivity have the potential to provide incremental revenue opportunities for us. These technologies may include edge computing functionality, autonomous vehicle networks and a number of other internet-of-things, or IoT, applications, as well as other potential use cases for wireless services. These technologies may create new and complementary use cases for our communications real estate over time, although these use cases are currently in nascent stages.
Continued data growth and emerging high-performance, latency-sensitive applications will drive an increased need for reliable, secure and interconnected data center solutions. We believe these trends will result in incremental utilization and interconnection demand at our data center facilities.
As part of our international expansion initiatives, we have targeted markets in various stages of network development to diversify our international exposure and position us to benefit from a number of different wireless technology deployments over the long term. In addition, we have focused on building relationships with large multinational carriers to increase the opportunities for growth or mutually beneficial transactional opportunities across common markets. We believe that consistent carrier network investments across our international markets will, over the long term, position us to generate meaningful organic revenue growth going forward.
In emerging markets, such as Bangladesh, Burkina Faso, Ghana, India, Kenya, Niger, Nigeria, the Philippines and Uganda, wireless networks tend to be significantly less advanced than those in the United States, and initial voice networks continue to be deployed in certain underdeveloped areas. A majority of consumers in these markets still utilize basic wireless services and advanced device penetration remains low. In more developed urban locations within these markets, mobile data usage tends to be higher and advanced network deployments are further along. Carriers are focused on completing voice network build-outs while increasing investments in data networks as mobile data usage and smartphone penetration within their customer bases begin to accelerate.
In India, the ongoing transition from 2G technology to 4G technology has included a period of carrier consolidation, whereby the number of carriers operating in the marketplace has been reduced through mergers, acquisitions and select carrier exits from the marketplace, which we believe is now substantially complete. We believe that this consolidation process has resulted in an industry structure for both the wireless carriers and communications infrastructure providers that will be more conducive to sustained growth and profitability over time.
In markets with rapidly evolving network technology, such as South Africa, Poland and most of the countries in Latin America where we do business, initial voice networks, for the most part, have already been built out, and carriers are increasingly focused on 4G network deployments. Consumers in these regions are increasingly adopting smartphones and other advanced devices, in particular as lower cost smartphones become increasingly available. As a result, the usage of bandwidth-intensive mobile applications is growing materially. Recent spectrum auctions in these rapidly evolving markets have allowed incumbent carriers to accelerate their data network deployments and have also enabled new entrants to begin initial investments in data networks. Smartphone penetration and wireless data usage in these markets are advancing rapidly, which typically requires that carriers continue to invest in their networks to maintain and augment their quality of service.
Finally, in markets with more mature network technology, such as Australia, Canada, Germany, France and Spain, carriers are focused on deploying 4G data networks to account for rapidly increasing wireless data usage among their customer base. With higher smartphone and advanced device penetration and significantly higher per capita data usage, carrier investment in networks is focused on 4G coverage and capacity, as well as the early stages of 5G deployment.
We believe that the network technology migration we have seen in the United States, which has led to significantly denser networks and meaningful new business commencements for us over a number of years, will be replicated in our international markets over time. As a result, we expect to be able to leverage our extensive international portfolio of approximately 177,000 communications sites and the relationships we have built with our carrier tenants to drive sustainable, long-term growth.
We have master lease agreements with many of our tenants for our communications sites that provide for consistent, long-term revenue and reduce the likelihood of non-contractual churn. Certain of those master lease agreements are comprehensive in nature and further build and augment strong strategic partnerships with our tenants while significantly reducing colocation cycle times, thereby providing our tenants with the ability to rapidly and efficiently deploy equipment on our sites.
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Demand for our communications infrastructure assets could be negatively impacted by a number of factors, including an increase in network sharing or consolidation among our customers, as set forth in Item 1A of this Annual Report under the captions “Risk Factors—If our customers consolidate their operations, exit their businesses or share site infrastructure to a significant degree, our growth, revenue and ability to generate positive cash flows could be materially and adversely affected” and “Risk Factors—A substantial portion of our revenue is derived from a small number of customers, and we are sensitive to adverse changes in the creditworthiness and financial strength of our customers.” In addition, the emergence and growth of new technologies could reduce demand for our sites, as set forth under the caption “Risk Factors—New technologies or changes in our or a customer’s business model could make our communications infrastructure leasing business less desirable and result in decreasing revenues and operating results.” Further, our customers may be subject to new regulatory policies from time to time that materially and adversely affect the demand for our communications infrastructure assets.
Property Operations New Site Revenue Growth. During the year ended December 31, 2021, we grew our portfolio of communications real estate through the acquisition and construction of approximately 38,950 communications sites globally. In a majority of our Asia-Pacific, Africa, Europe and Latin America markets, the revenue generated from newly acquired or constructed sites resulted in increases in both tenant and pass-through revenues (such as ground rent or power and fuel costs) and expenses. We continue to evaluate opportunities to acquire communications real estate portfolios, both domestically and internationally, to determine whether they meet our risk-adjusted hurdle rates and whether we believe we can effectively integrate them into our existing portfolio.
New Sites (Acquired or Constructed)202120202019
U.S. & Canada170 2,255 430 
Asia-Pacific3,780 3,960 3,330 
Africa2,355 1,540 6,455 
Europe24,775 610 15 
Latin America7,870 1,000 3,475 
During the year ended December 31, 2021, we also grew our portfolio of data center facilities through the acquisition of over 20 data center facilities and related assets in the United States, including through the CoreSite Acquisition.
Property Operations Expenses. Direct operating expenses incurred by our property segments include direct site or facility level expenses and consist primarily of ground rent and power and fuel costs, some or all of which may be passed through to our customers, as well as property taxes and repairs and maintenance expenses. These segment direct operating expenses exclude all segment and corporate selling, general, administrative and development expenses, which are aggregated into one line item entitled Selling, general, administrative and development expense in our consolidated statements of operations. In general, our property segments’ selling, general, administrative and development expenses do not significantly increase as a result of adding incremental customers to our sites or facilities and typically increase only modestly year-over-year. As a result, leasing additional space to new customers on our sites or within our facilities provides significant incremental gross margin and cash flow. We may, however, incur additional segment selling, general, administrative and development expenses as we increase our presence in our existing markets or expand into new markets. Our profit margin growth is therefore positively impacted by the addition of new customers to our sites or facilities but can be temporarily diluted by our development activities.
Services Segment Revenue Growth. As we continue to focus on growing our property operations, we anticipate that our services revenue will continue to represent a small percentage of our total revenues.
Non-GAAP Financial Measures
Included in our analysis of our results of operations are discussions regarding earnings before interest, taxes, depreciation, amortization and accretion, as adjusted (“Adjusted EBITDA”), Funds From Operations, as defined by the National Association of Real Estate Investment Trusts (“Nareit FFO”) attributable to American Tower Corporation common stockholders, Consolidated Adjusted Funds From Operations (“Consolidated AFFO”) and AFFO attributable to American Tower Corporation common stockholders.
We define Adjusted EBITDA as Net income before Income (loss) from equity method investments; Income tax benefit (provision); Other income (expense); Gain (loss) on retirement of long-term obligations; Interest expense; Interest income; Other operating income (expense); Depreciation, amortization and accretion; and stock-based compensation expense.
Nareit FFO attributable to American Tower Corporation common stockholders is defined as net income before gains or losses from the sale or disposal of real estate, real estate related impairment charges, real estate related depreciation, amortization and accretion and dividends on preferred stock, and including adjustments for (i) unconsolidated affiliates and (ii) noncontrolling
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interests. In this section, we refer to Nareit FFO attributable to American Tower Corporation common stockholders as “Nareit FFO (common stockholders).”
We define Consolidated AFFO as Nareit FFO (common stockholders) before (i) straight-line revenue and expense; (ii) stock-based compensation expense; (iii) the deferred portion of income tax and other income tax adjustments; (iv) non-real estate related depreciation, amortization and accretion; (v) amortization of deferred financing costs, capitalized interest, debt discounts and premiums and long-term deferred interest charges; (vi) other income (expense); (vii) gain (loss) on retirement of long-term obligations; (viii) other operating income (expense); and adjustments for (ix) unconsolidated affiliates and (x) noncontrolling interests, less cash payments related to capital improvements and cash payments related to corporate capital expenditures.
We define AFFO attributable to American Tower Corporation common stockholders as Consolidated AFFO, excluding the impact of noncontrolling interests on both Nareit FFO (common stockholders) and the other adjustments included in the calculation of Consolidated AFFO. In this section, we refer to AFFO attributable to American Tower Corporation common stockholders as “AFFO (common stockholders).”
Adjusted EBITDA, Nareit FFO (common stockholders), Consolidated AFFO and AFFO (common stockholders) are not intended to replace net income or any other performance measures determined in accordance with GAAP. None of Adjusted EBITDA, Nareit FFO (common stockholders), Consolidated AFFO or AFFO (common stockholders) represents cash flows from operating activities in accordance with GAAP and, therefore, these measures should not be considered indicative of cash flows from operating activities, as a measure of liquidity or a measure of funds available to fund our cash needs, including our ability to make cash distributions. Rather, Adjusted EBITDA, Nareit FFO (common stockholders), Consolidated AFFO and AFFO (common stockholders) are presented as we believe each is a useful indicator of our current operating performance. We believe that these metrics are useful to an investor in evaluating our operating performance because (1) each is a key measure used by our management team for decision making purposes and for evaluating our operating segments’ performance; (2) Adjusted EBITDA is a component underlying our credit ratings; (3) Adjusted EBITDA is widely used in the telecommunications real estate sector to measure operating performance as depreciation, amortization and accretion may vary significantly among companies depending upon accounting methods and useful lives, particularly where acquisitions and non-operating factors are involved; (4) Consolidated AFFO is widely used in the telecommunications real estate sector to adjust Nareit FFO (common stockholders) for items that may otherwise cause material fluctuations in Nareit FFO (common stockholders) growth from period to period that would not be representative of the underlying performance of property assets in those periods; (5) each provides investors with a meaningful measure for evaluating our period-to-period operating performance by eliminating items that are not operational in nature; and (6) each provides investors with a measure for comparing our results of operations to those of other companies, particularly those in our industry.
Our measurement of Adjusted EBITDA, Nareit FFO (common stockholders), Consolidated AFFO and AFFO (common stockholders) may not, however, be fully comparable to similarly titled measures used by other companies. Reconciliations of Adjusted EBITDA, Nareit FFO (common stockholders), Consolidated AFFO and AFFO (common stockholders) to net income, the most directly comparable GAAP measure, have been included below.
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Results of Operations
Year Ended December 31, 2020 Compared to Year Ended December 31, 2019
For a discussion of our 2020 Results of Operations, including a discussion of our financial results for the fiscal year ended December 31, 2020 compared to the fiscal year ended December 31, 2019, refer to Part I, Item 7 of our annual report on Form 10-K filed with the SEC on February 25, 2021 (the “2020 Form 10-K”).
During the fourth quarter of 2021, as a result of the CoreSite Acquisition, we updated our reportable segments to add a Data Centers segment. The Data Centers segment is included within our property operations. We will now report our results in seven segments – U.S. & Canada property (which includes all assets in the United States and Canada, other than our data center facilities and related assets), Asia-Pacific property, Africa property, Europe property, Latin America property, Data Centers and Services. We believe this change provides greater visibility into our operating segments and aligns our reporting with management’s current approach of allocating costs and resources, managing growth and profitability and assessing the operating performance of our business segments. This change applies to our business operations results beginning with the fourth quarter of 2021 and had no impact on our consolidated financial statements for any prior periods. Historical financial information included in this Annual Report has not been adjusted as the amounts attributable to data center assets were insignificant as prior to to the fourth quarter of 2021, we owned one data center.    

Years Ended December 31, 2021 and 2020
(in millions, except percentages)
Revenue
 Year Ended December 31,Percent Change 2021 vs 2020
 20212020
Property
U.S. & Canada (1)$4,920.2 $4,517.0 %
Asia-Pacific1,199.1 1,139.4 
Africa1,005.5 890.2 13 
Europe496.2 149.6 232 
Latin America1,465.4 1,257.4 17 
Data Centers23.2 — 100 
Total property9,109.6 7,953.6 15 
Services247.3 87.9 181 
Total revenues$9,356.9 $8,041.5 16 %
_______________
(1)    For the year ended December 31, 2020, U.S. & Canada includes $8.5 million of revenue attributable to our data center assets. For the year ended December 31, 2021, revenue attributable to our data center assets previously reported in the U.S. & Canada property segment is now shown in the Data Centers segment.
Year ended December 31, 2021
U.S. & Canada property segment revenue growth of $403.2 million was attributable to:
Tenant billings growth of $287.6 million, which was driven by:
$168.2 million generated from newly acquired or constructed sites, primarily related to our acquisition of InSite Wireless Group, LLC (“InSite,” and the acquisition, the “InSite Acquisition”); and
$129.4 million due to colocations and amendments;
Partially offset by:
A decrease of $7.7 million from other tenant billings; and
A decrease of $2.3 million from churn in excess of contractual escalations (as discussed above, we expect that our churn rate will be elevated for a period of several years due to the terms of the T-Mobile MLA); and
An increase of $115.6 million in other revenue, which includes a $143.7 million increase due to straight-line accounting, primarily due to the impact of the T-Mobile MLA, partially offset by a decrease in revenue attributable to our data center assets, which is presented in the Data Centers segment in the current period.
Segment revenue growth was not meaningfully impacted by foreign currency translation related to fluctuations in the Canadian Dollar. During the year ended December 31, 2021, the assets acquired pursuant to the InSite Acquisition generated approximately $153.7 million in U.S. & Canada property revenue.
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Asia-Pacific property segment revenue growth of $59.7 million was attributable to:
An increase of $41.6 million in pass-through revenue; and
Tenant billings growth of $22.7 million, which was driven by:
$48.2 million due to colocations and amendments; and
$24.7 million generated from newly acquired or constructed sites;
Partially offset by:
A decrease of $49.1 million resulting from churn in excess of contractual escalations; and
A decrease of $1.1 million from other tenant billings;
Partially offset by a decrease of $6.8 million in other revenue, primarily due to tenant settlements in the prior-year period.
Segment revenue growth included an increase of $2.2 million attributable to the positive impact of foreign currency translation related to fluctuations in Indian Rupee (“INR”).
Africa property segment revenue growth of $115.3 million was attributable to:
Tenant billings growth of $90.6 million, which was driven by:
$40.2 million due to colocations and amendments;
$39.0 million generated from newly acquired or constructed sites;
$7.6 million from contractual escalations, net of churn; and
$3.8 million from other tenant billings; and
An increase of $44.9 million in pass-through revenue;
Partially offset by a decrease of $23.1 million in other revenue, primarily due to an increase in revenue reserves and a decrease in tenant settlements attributable to prior tenant cancellations.
Segment revenue growth included an increase of $2.9 million attributable to the impact of foreign currency translation, which included, among others, positive impacts of $16.0 million related to fluctuations in South African Rand, partially offset by negative impacts related to fluctuations in the currencies of our other African markets, which included, among others, $12.2 million related to fluctuations in Nigerian Naira.
Europe property segment revenue growth of $346.6 million was attributable to:
Tenant billings growth of $196.3 million, which was driven by:
$189.8 million generated from newly acquired or constructed sites, primarily attributable to the Telxius Acquisition and our agreements with Orange S.A. (“Orange”);
$7.9 million due to colocations and amendments; and
$0.1 million from other tenant billings;
Partially offset by a decrease of $1.5 million resulting from churn in excess of contractual escalations;
An increase of $128.9 million in pass-through revenue, primarily attributable to the Telxius Acquisition; and
An increase of $14.9 million in other revenue, primarily attributable to straight-line accounting, the Telxius Acquisition and increases in back-billing.
Segment revenue growth included an increase of $6.5 million, primarily attributable to the positive impact of foreign currency translation related to fluctuations in EUR. During the year ended December 31, 2021, the assets acquired pursuant to the Telxius Acquisition generated approximately $318.0 million in Europe property revenue.
Latin America property segment revenue growth of $208.0 million was attributable to:
Tenant billings growth of $114.5 million, which was driven by:
$49.3 million generated from newly acquired or constructed sites, primarily attributable to the Telxius Acquisition;
$33.8 million due to colocations and amendments;
$27.9 million from contractual escalations, net of churn; and
$3.5 million from other tenant billings;
An increase of $72.3 million in pass-through revenue, primarily attributable to increased pass-through ground rent costs in Brazil and the Telxius Acquisition; and
An increase of $27.2 million in other revenue primarily as a result of a tenant settlement in Brazil.
Segment revenue growth included a decrease of $6.0 million, attributable to the impact of foreign currency translation, which included, among others, negative impacts of $28.0 million related to fluctuations in Brazilian Real and $4.8 million related to fluctuations in Peruvian Sol, partially offset by positive impacts related to fluctuations in the currencies of our other Latin American markets, which included, among others, $25.3 million related to fluctuations in Mexican Peso. During the year ended December 31, 2021, the assets acquired pursuant to the Telxius Acquisition generated approximately $70.7 million in Latin America property revenue.
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Data Centers segment revenue growth was attributable to data centers acquired in 2021, including through the CoreSite Acquisition.
Services segment revenue growth of $159.4 million was primarily attributable to an increase in site application, zoning, permitting and structural analysis services.
Gross Margin
 Year Ended December 31,Percent Change 2021 vs 2020
 20212020
Property
U.S. & Canada (1)$4,066.7 $3,709.0 10 %
Asia-Pacific474.8 478.0 (1)
Africa659.4 592.5 11 
Europe302.2 121.5 149 
Latin America1,007.1 864.9 16 
Data Centers14.1 — 100 
Total property6,524.3 5,765.9 13 
Services150.6 51.4 193 %
_______________
(1)    For the year ended December 31, 2020, U.S. & Canada included $6.0 million of gross margin attributable to our data center assets. For the year ended December 31, 2021, gross margin attributable to our data center assets previously reported in the U.S. & Canada property segment is now shown in the Data Centers segment.
Year ended December 31, 2021
The increase in U.S. & Canada property segment gross margin was primarily attributable to the increase in revenue described above, partially offset by an increase in direct expenses of $45.5 million, including expenses due to the InSite Acquisition.
The decrease in Asia-Pacific property segment gross margin was primarily attributable to an increase in direct expenses of $61.5 million, primarily due to an increase in costs associated with pass-through revenue, including fuel costs, partially offset by the increase in revenue described above. Direct expenses were also negatively impacted by $1.4 million from the impact of foreign currency translation.
The increase in Africa property segment gross margin was primarily attributable to the increase in revenue described above, partially offset by an increase in direct expenses of $50.0 million. Direct expenses also benefited by $1.6 million from the impact of foreign currency translation.
The increase in Europe property segment gross margin was primarily attributable to the increase in revenue described above, partially offset by an increase in direct expenses of $164.7 million, primarily due to the Telxius Acquisition. Direct expenses were also negatively impacted by $1.2 million from the impact of foreign currency translation.
The increase in Latin America property segment gross margin was primarily attributable to the increase in revenue described above, partially offset by an increase in direct expenses of $69.6 million, including expenses related to the Telxius Acquisition. Direct expenses also benefited by $3.8 million from the impact of foreign currency translation.
The increase in Data Centers segment gross margin was attributable to data centers acquired in 2021, including through the CoreSite Acquisition.
The increase in Services segment gross margin was primarily due to the increase in revenue described above, partially offset by an increase in direct expenses of $60.2 million.
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Selling, General, Administrative and Development Expense (“SG&A”)
 Year Ended December 31,Percent Change 2021 vs 2020
 20212020
Property
U.S. & Canada (1)$176.9 $162.2 %
Asia-Pacific73.1 97.4 (25)
Africa72.3 94.4 (23)
Europe42.1 23.0 83 
Latin America104.1 93.1 12 
Data Centers5.9 — 100 
Total property474.4 470.1 
Services16.2 14.8 
Other 321.0 293.8 
Total selling, general, administrative and development expense$811.6 $778.7 %
_______________
(1)    For the year ended December 31, 2020, U.S. & Canada included $3.2 million of SG&A attributable to our data center assets. For the year ended December 31, 2021, SG&A attributable to our data center assets previously reported in the U.S. & Canada property segment is now shown in the Data Centers segment.
Year Ended December 31, 2021
The increase in our U.S. & Canada property segment SG&A was primarily driven by increased personnel costs to support our business, including as a result of the InSite Acquisition, partially offset by lower canceled construction costs.
The decrease in our Asia-Pacific property segment SG&A was primarily driven by a decrease in bad debt expense of $35.2 million.
The decrease in our Africa property segment SG&A was primarily driven by a decrease in bad debt expense of $26.3 million.
The increase in our Europe property segment SG&A was primarily driven by increased personnel costs to support our business, including as a result of the Telxius Acquisition.
The increase in our Latin America property segment SG&A was primarily driven by an increase in bad debt expense of $8.3 million, as a result of receivable reserves with a tenant.
The increase in our Data Centers segment SG&A was attributable to data centers acquired in 2021, including through the CoreSite Acquisition.
The increase in our Services segment SG&A was primarily driven by an increase in personnel costs to support our business.
The increase in other SG&A was primarily driven by an increase in corporate SG&A, including an increase in personnel costs to support our business.
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Table of Contents
Operating Profit
 Year Ended December 31,Percent Change 2021 vs 2020
 20212020
Property
U.S. & Canada (1)$