interest rate swaps and swaptions to help manage our funding cost on our investments in the event that interest rates rise. These swaps (or swaptions) allow us to reduce our funding exposure on the notional amount of the swap for a specified period of time by establishing a fixed rate to pay in exchange for receiving a floating rate that generally tracks our financing costs under our repurchase agreements.
However, if prepayment rates decrease in a rising interest rate environment, the average life or duration of our fixed rate assets generally extends. This could have a negative impact on our results from operations, as our interest rate swap maturities are fixed and will, therefore, cover a smaller percentage of our funding exposure on our mortgage assets to the extent that their average lives increase due to slower prepayments. This situation may also cause the market value of our fixed rate agency securities to decline by more than otherwise would be the case while most of our hedging instruments would not receive any incremental offsetting gains. In extreme situations, we may be forced to sell assets to maintain adequate liquidity, which could cause us to incur realized losses.
Counterparty Credit Risk
We are exposed to counterparty credit risk relating to potential losses that could be recognized in the event that the counterparties to our repurchase agreements and derivative contracts fail to perform their obligations under such agreements. The amount of assets we pledge as collateral in accordance with our agreements varies over time based on the market value and notional amount of such assets as well as the value of our derivative contracts. In the event of a default by a counterparty, we may not receive payments provided for under the terms of our agreements and may have difficulty obtaining our assets pledged as collateral under such agreements. Our credit risk related to certain derivative transactions is largely mitigated through daily adjustments to collateral pledged based on changes in market value and we limit our counterparties to major financial institutions with acceptable credit ratings. However, there is no guarantee our efforts to manage counterparty credit risk will be successful and we could suffer significant losses if unsuccessful.
Item 4. Controls and Procedures
We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our Securities Exchange Act of 1934, as amended (the "Exchange Act") reports is recorded, processed, summarized and reported within the time periods specified in the SEC's rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure based on the definition of "disclosure controls and procedures" as promulgated under the Exchange Act and the rules and regulations thereunder. In designing and evaluating the disclosure controls and procedures, management recognized that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management necessarily was required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures.
We, including our Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of the design and operation of our disclosure controls and procedures as of March 31, 2015. Based on the foregoing, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective.
Changes in Internal Controls over Financial Reporting
There have been no changes in our "internal control over financial reporting" (as defined in Rule 13a-15(f) of the Exchange Act) that occurred during the last fiscal quarter that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.