Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Our primary exposures to market risks are related to changes in interest rates, which may adversely affect our results of operations and financial position. We seek to manage exposure to changes in interest rates where economically prudent to do so by utilizing fixed rate debt.

Our interest rate risk as of December 31, 2020 relates primarily to the impact of interest rate movements on the following, after giving effect to our February 2021 Senior Notes offering and the use of the net proceeds therefrom:

• the potential refinancing of our $19.7 billion in existing debt, compared to $18.2 billion in the prior year;

• our $1.5 billion of floating rate debt representing approximately 8% of total debt, compared to 16% in the prior year; and

• potential future borrowings of incremental debt, including borrowings under our 2016 Credit Facility and issuances under the CP Program.

Potential Refinancing of Existing Debt

We have no significant contractual debt maturities (or anticipated repayment dates on our Tower Revenue Notes) over the next 12 months, other than Commercial Paper Notes and principal payments on certain outstanding debt. As of December 31, 2020 and December 31, 2019, we had no interest rate swaps hedging any refinancings. See below for a tabular presentation of our scheduled contractual debt maturities as of December 31, 2020 and a discussion of anticipated repayment dates.

Floating Rate Debt

We manage our exposure to market interest rates on our existing debt by controlling the mix of fixed and floating rate debt. As of December 31, 2020, after giving effect to our February 2021 Senior Notes offering and the use of the net proceeds therefrom, we had $1.5 billion of floating rate debt, none of which had LIBOR floors. As a result, a hypothetical unfavorable fluctuation in market interest rates on our existing debt of 1/8 of a percent point over a 12-month period would increase our interest expense by approximately $2 million. As of December 31, 2019, we had approximately $3.0 billion of floating rate debt, none of which had LIBOR floors. See also "Item 1A. Risk Factors" for a discussion of uncertainty related to the continued use of LIBOR.

Potential Future Borrowings of Incremental Debt

We typically do not hedge our exposure to interest rates on potential future borrowings of incremental debt for a substantial period prior to issuance. See "Item 7. MD&A—Liquidity and Capital Resources" regarding our liquidity strategy.

The following table provides information about our market risk related to changes in interest rates, after giving effect to our February 2021 Senior Notes offering and the use of the net proceeds therefrom. The future principal payments and weighted-average interest rates are presented as of December 31, 2020. These debt maturities reflect contractual maturity dates, and do not consider the impact of the principal payments that will commence following the anticipated repayment dates of certain debt (see footnotes (b) and (d)). See note 7 to our consolidated financial statements for additional information regarding our debt.

(a)The fair value of our debt is based on indicative quotes (that is, non-binding quotes) from brokers that require judgment to interpret market information, including implied credit spreads for similar borrowings on recent trades or bid/ask offers. These fair values are not necessarily indicative of the amount, which could be realized in a current market exchange.

(b)The impact of principal payments that will commence following the anticipated repayment dates is not considered. The Tower Revenue Notes have principal amounts of $300 million, $250 million, $700 million and $750 million, with anticipated repayment dates in 2022, 2023, 2025 and 2028, respectively.

(c)The average interest rate represents the weighted-average stated coupon rate (see also footnote (d)).

(d) If the Tower Revenue Notes are not repaid in full by the applicable anticipated repayment dates, the applicable interest rate increases by approximately 5% per annum and monthly principal payments commence using the Excess Cash Flow (as defined in the indenture governing the applicable Tower Revenue Notes) of the issuers of the Tower Revenue Notes. The Tower Revenue Notes are presented based on their contractual maturity dates ranging from 2042 to 2048 and include the impact of an assumed 5% increase in interest rate that would occur following the anticipated repayment dates but exclude the impact of monthly principal payments that would commence using Excess Cash Flow of the issuers of the Tower Revenue Notes The full year 2020 Excess Cash Flow of the issuers of the Tower Revenue Notes was approximately $815 million. We currently expect to refinance these notes on or prior to the respective anticipated repayment dates.

(e) Consists of our senior unsecured term loan A facility ("2016 Term Loan A") and our 2016 Revolver borrowings, each of which matures in 2024.