CASH 2018 Annual Report

24 While MBS carry a reduced credit risk as compared to whole loans, such securities remain subject to the risk that a fluctuating interest rate environment, along with other factors such as the geographic distribution and other underwriting risks inherent in the underlying mortgage loans, may alter the prepayment rate of such mortgage loans and so affect both the prepayment speed, and value, of such securities. The prepayment risk associated with MBS is continually monitored, and prepayment rate assumptions are adjusted as appropriate to update the Company’s MBS accounting and asset/liability reports. The following table sets forth the carrying value of the Company’s MBS at the dates indicated. At September 30, 2018 2017 2016 Available for Sale (Dollars in Thousands) Farmer Mac $ 52,849 $ — $ — Freddie Mac 69,575 100,287 164,577 Fannie Mae 241,641 486,167 394,363 Total AFS $ 364,065 $ 586,454 $ 558,940 At September 30, 2018 2017 2016 Held to Maturity (Dollars in Thousands) Farmer Mac $ — $ 61,295 $ 71,011 Fannie Mae — 43,458 51,894 Ginnie Mae 7,850 8,936 10,853 Total HTM $ 7,850 $ 113,689 $ 133,758