Item 3. Quantitative and Qualitative Disclosures About Market Risk

We are exposed to various market risks, including the potential loss arising from adverse changes in interest rates. We use derivative and other financial instruments in the normal course of business to mitigate interest rate risk. We do not use derivative financial instruments for speculative or trading purposes. Derivatives are recorded on the Consolidated Balance Sheets at fair value (see Note 18 to the Consolidated Financial Statements).

Interest Rate Risk. At September 30, 2021, our exposure to interest rate risk is primarily on our variable rate debt. At September 30, 2021, $142 million of our variable-rate debt was subject to interest rate cap agreements. The interest rate caps are non-designated hedges and manage our exposure to variable cash flows on certain mortgage debt borrowings by limiting interest rates. At September 30, 2021, both the fair value and carrying value of the interest rate caps were $0.2 million.

Our remaining variable rate debt at September 30, 2021 was comprised of our bank line of credit, commercial paper program, and certain of our mortgage debt. Interest rate fluctuations will generally not affect our future earnings or cash flows on our fixed rate debt and assets until their maturity or earlier prepayment and refinancing. If interest rates have risen at the time we seek to refinance our fixed rate debt, whether at maturity or otherwise, our future earnings and cash flows could be adversely affected by additional borrowing costs. Conversely, lower interest rates at the time of refinancing may reduce our overall borrowing costs. However, interest rate changes will affect the fair value of our fixed rate instruments. At September 30, 2021, a one percentage point increase or decrease in interest rates would change the fair value of our fixed rate debt by approximately $291 million and $317 million, respectively, and would not materially impact earnings or cash flows. Conversely, changes in interest rates on variable rate debt and investments would change our future earnings and cash flows, but not materially impact the fair value of those instruments. Assuming a one percentage point change in the interest rate related to our variable-rate debt and variable-rate investments, and assuming no other changes in the outstanding balance at September 30, 2021, our annual interest expense would change by up to approximately $12 million.

Market Risk. We have investments in marketable debt securities classified as held-to-maturity because we have the positive intent and ability to hold the securities to maturity. Held-to-maturity securities are recorded at amortized cost and adjusted for the amortization of premiums and discounts through maturity. We consider a variety of factors in evaluating an other-than-temporary decline in value, such as: the length of time and the extent to which the market value has been less than our current adjusted carrying value; the issuer’s financial condition, capital strength, and near-term prospects; any recent events specific to that issuer and economic conditions of its industry; and our investment horizon in relationship to an anticipated near-term recovery in the market value, if any. At September 30, 2021, both the fair value and carrying value of marketable debt securities was $21 million.