SECURITIES

Amortized cost and estimated fair value of securities available for sale at December 31, 2019 and 2018 are as follows (in thousands):



	2019				2018
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Obligations of U.S. Government and U.S. Government sponsored enterprises	$	—	$	—	$	5,489	$	5,472
Mortgage-backed securities, residential	225,029		225,234		189,111		183,192
Obligations of states and political subdivisions	41,265		42,845		44,390		44,152
Corporate bonds and notes	250		250		249		247
SBA loan pools	15,712		15,761		9,257		9,195
Total	$	282,256	$	284,090	$	248,496	$	242,258

Gross unrealized gains and losses on securities available for sale at December 31, 2019 and 2018, were as follows (in thousands):



	2019				2018
	Unrealized Gains		Unrealized Losses		Unrealized Gains		Unrealized Losses
Obligations of U.S. Government and U.S. Government sponsored enterprises	$	—	$	—	$	10	$	27
Mortgage-backed securities, residential	1,471		1,266		146		6,065
Obligations of states and political subdivisions	1,580		—		70		308
Corporate bonds and notes	—		—		—		2
SBA loan pools	95		46		—		62
Total	$	3,146	$	1,312	$	226	$	6,464

The amortized cost and estimated fair value of debt securities available for sale are shown below by contractual maturity. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately (in thousands):



	December 31, 2019
	Amortized Cost		Fair Value
Within one year	$	725	$	726
After one, but within five years	7,095		7,324
After five, but within ten years	32,646		33,968
After ten years	1,049		1,077
Mortgage-backed securities, residential	225,029		225,234
SBA loan pools	15,712		15,761
Total	$	282,256	$	284,090

Actual maturities may differ from contractual maturities above because issuers may have the right to call or prepay obligations with or without call or prepayment penalties.

The proceeds from sales and calls of securities resulting in gains or losses are listed below (in thousands):



	2019			2018		2017
Proceeds	$	8,513		$	—	$	5,576
Gross gains	$	159		$	—	$	109
Gross losses	$	(140	)	$	—	$	—
Tax expense	$	5		$	—	$	41

Amortized cost and estimated fair value of securities held to maturity at December 31, 2019 and 2018 are as follows (in thousands):



	2019				2018
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Obligations of states and political subdivisions	$	1,045	$	1,045	$	3,020	$	3,020
Time deposits with other financial institutions	2,070		2,094		1,855		1,838
	$	3,115	$	3,139	$	4,875	$	4,858

Gross unrealized gains and losses on securities held to maturity at December 31, 2019 and 2018, were as follows (in thousands):



	2019				2018
	Unrealized Gains		Unrealized Losses		Unrealized Gains		Unrealized Losses
Obligations of states and political subdivisions	$	—	$	—	$	—	$	—
Time deposits with other financial institutions	24		—		—		17
Total	$	24	$	—	$	—	$	17

There were no sales of securities held to maturity in 2019 or 2018.

The contractual maturity of securities held to maturity is as follows at December 31, 2019 (in thousands):



	December 31, 2019
	Amortized Cost		Fair Value
Within one year	$	1,583	$	1,589
After one, but within five years	1,532		1,550
After five, but within ten years	—		—
After ten years	—		—
Total	$	3,115	$	3,139

The following table summarizes the investment securities available for sale with unrealized losses at December 31, 2019 and December 31, 2018 by aggregated major security type and length of time in a continuous unrealized position (in thousands):



	Less than 12 months				12 months or longer				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
2019	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Obligations of U.S. Government and U.S. Government sponsored enterprises	$	—	$	—	$	—	$	—	$	—	$	—
Mortgage-backed securities, residential	71,506		791		54,343		475		125,849		1,266
Obligations of states and political subdivisions	—		—		—		—		—		—
Corporate bonds and notes	—		—		—		—		—		—
SBA loan pools	3,014		9		1,405		37		4,419		46
Total temporarily impaired securities	$	74,520	$	800	$	55,748	$	512	$	130,268	$	1,312



	Less than 12 months				12 months or longer				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
2018	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Obligations of U.S. Government and U.S. Government sponsored enterprises	$	—	$	—	$	4,969	$	27	$	4,969	$	27
Mortgage-backed securities, residential	—		—		171,481		$	6,065	171,481		6,065
Obligations of states and political subdivisions	10,868		38		21,345		270		32,213		308
Corporate bonds and notes	247		2		—		—		247		2
SBA loan pools	5,985		17		3,210		45		9,195		62
Total temporarily impaired securities	$	17,100	$	57	$	201,005	$	6,407	$	218,105	$	6,464

Other-Than-Temporary-Impairment

As of December 31, 2019, the majority of the Corporation’s unrealized losses in the investment securities portfolio related to mortgage-backed securities. At December 31, 2019, all of the unrealized losses related to mortgage-backed securities were issued by U.S. government sponsored entities, Fannie Mae and Freddie Mac. Because the decline in fair value is attributable to changes in interest rates and not credit quality, and because the Corporation does not have the intent to sell these securities and it is not likely that it will be required to sell these securities before their anticipated recovery, the Corporation does not consider these securities to be other-than-temporarily impaired at December 31, 2019.

Pledged Securities

The fair value of securities pledged to secure public funds on deposit or for other purposes as required by law was $205.9 million at December 31, 2019 and $212.7 million at December 31, 2018.

There are no securities pledged to secure securities sold under agreements to repurchase at December 31, 2019 and 2018, respectively.

Concentrations

There are no securities of a single issuer (other than securities of U.S. Government sponsored enterprises) that exceed 10% of shareholders' equity at December 31, 2019 or 2018.

Equity Method Investments

The Corporation has an equity investment in Cephas Capital Partners, L.P. This small business investment company was established for the purpose of providing financing to small businesses in market areas served by the Corporation, including minority-owned small businesses and those that are anticipated to create jobs for the low to moderate income levels in the targeted areas. As of December 31, 2019 and 2018, this investment totaled $0.3 million and $0.4 million respectively, is included in other assets, and is accounted for under the equity method of accounting.