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 17 to the Consolidated Financial Statements).

To illustrate the effect of movements in the interest rate markets, we performed a market sensitivity analysis on our hedging instruments. We applied various basis point spreads to the underlying interest rate curves of our derivative portfolio in order to determine the change in fair value. At September 30, 2023, a one percentage point increase or decrease in the underlying interest rate curve would result in a corresponding increase or decrease in the fair value of the derivative instruments by up to approximately $19 million.

Interest Rate Risk. At September 30, 2023, our exposure to interest rate risk was primarily on our variable rate debt. At September 30, 2023, $142 million of our variable rate mortgage debt and our $500 million Term Loan Facilities were swapped to fixed rates through interest rate swap instruments. The interest rate swap instruments are designated as cash flow hedges, with the objective of managing the exposure to interest rate risk by converting the interest rates on our variable rate debt to fixed interest rates. At September 30, 2023, both the fair value and carrying value of the interest rate swap instruments were $39 million.

Our remaining variable rate debt at September 30, 2023 was comprised of borrowings under our 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. Interest rate changes will affect the fair value of our fixed rate instruments. At September 30, 2023, a one percentage point increase in interest rates would decrease the fair value of our fixed rate debt by approximately $231 million and a one percentage point decrease in interest rates would increase the fair value of our fixed rate debt by approximately $247 million. These changes would not materially impact earnings or cash flows. Conversely, changes in interest rates on variable rate debt would change our future earnings and cash flows, but not materially impact the fair value of those instruments. Assuming a one percentage point increase in the interest rates related to our variable rate debt, and assuming no other changes in the outstanding balance at September 30, 2023, our annual interest expense would increase by approximately $4 million. Lastly, assuming a one percentage point decrease in the interest rates related to our variable rate loans receivable, and assuming no other changes in the outstanding balance at September 30, 2023, our annual interest income would decrease by approximately $2 million.