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3) Investments: Investments Classified by Contractual Maturity Date (Details) - USD ($) | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Amortized Cost | $ 327,205,498 | $ 323,056,426
Held to maturity securities, Estimated fair value | 348,628,792 | 329,145,562
Due in 1 year |  |
Amortized Cost | 61,039,649 |
Held to maturity securities, Estimated fair value | 61,451,128 |
Due in 2-5 years |  |
Amortized Cost | 73,278,818 |
Held to maturity securities, Estimated fair value | 76,149,038 |
Due in 5-10 years |  |
Amortized Cost | 82,777,913 |
Held to maturity securities, Estimated fair value | 88,468,598 |
Due in more than 10 years |  |
Amortized Cost | 73,955,716 |
Held to maturity securities, Estimated fair value | 85,927,291 |
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises |  |
Amortized Cost | 35,789,063 | 31,475,280
Held to maturity securities, Estimated fair value | 36,264,337 | 31,832,498
Redeemable Preferred Stock |  |
Amortized Cost | 364,339 | 364,339
Held to maturity securities, Estimated fair value | $ 368,400 | $ 364,339

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