A summary of amortized cost and approximate fair value of investment securities available for sale included in the consolidated statements of condition as of December 31, 2020 and 2019 follows:

	2020
			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
(In thousands)	Cost		Gains		Losses			Value
U.S. treasuries	$	2,613	$	—	$	—		$	2,613
U.S. government-sponsored agencies		84,424		2		(655	)		83,771
Mortgage-backed securities-residential		467,915		8,604		(461	)		476,058
SBA pool securities		49,457		31		(359	)		49,129
State and political subdivisions		7,987		102		—			8,089
Corporate bond		3,000		29		—			3,029
Total	$	615,396	$	8,768	$	(1,475	)	$	622,689

	2019
			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
(In thousands)	Cost		Gains		Losses			Value
U.S. government-sponsored agencies	$	34,961	$	37	$	(214	)	$	34,784
Mortgage-backed securities-residential		337,489		2,365		(950	)		338,904
SBA pool securities		2,799		—		(15	)		2,784
State and political subdivisions		11,175		41		(1	)		11,215
Corporate bond		3,000		68		—			3,068
Total	$	389,424	$	2,511	$	(1,180	)	$	390,755

The amortized cost and fair value of investment securities available for sale as of December 31, 2020, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because borrowers may have the right to call or repay obligations with or without call or prepayment penalties. Securities not due at a single maturity, such as mortgage-backed securities, marketable equity securities are shown separately.

(In thousands)
Maturing in:	Amortized Cost		Fair Value
One year or less	$	5,500	$	5,515
After one year through five years		5,100		5,187
After five years through ten years		37,473		37,177
After ten years		49,951		49,623
		98,024		97,502
Mortgage-backed securities-residential		467,915		476,058
SBA pool securities		49,457		49,129
Total	$	615,396	$	622,689

Securities available for sale with a fair value of $598.3 million and $374.6 million as of December 31, 2020 and December 31, 2019, respectively, were pledged, but not necessarily encumbered, to secure public funds and for other purposes required or permitted by law.

The following is a summary of the gross gains, gross losses and net tax benefit related to proceeds on sales of securities available for sale for the years ended December 31:

(In thousands)	2020		2019		2018
Proceeds on sales	$	—	$	—	$	19,542
Gross gains		—		—		45
Gross losses		—		—		(333	)
Net tax benefit		—		—		(68	)

The following table presents the Company’s available for sale securities with continuous unrealized losses and the approximate fair value of these investments as of December 31, 2020 and 2019.

	2020
	Duration of Unrealized Loss
	Less Than 12 Months					12 Months or Longer					Total
	Approximate					Approximate					Approximate
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
(In thousands)	Value		Losses			Value		Losses			Value		Losses
U.S. government- sponsored agencies	$	73,769	$	(655	)	$	—	$	—		$	73,769	$	(655	)
Mortgage-backed securities-residential		103,340		(430	)		13,914		(31	)		117,254		(461	)
SBA pool securities		39,720		(343	)		2,095		(16	)		41,815		(359	)
Total	$	216,829	$	(1,428	)	$	16,009	$	(47	)	$	232,838	$	(1,475	)

	2019
	Duration of Unrealized Loss
	Less Than 12 Months					12 Months or Longer					Total
	Approximate					Approximate					Approximate
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
(In thousands)	Value		Losses			Value		Losses			Value		Losses
U.S. government- sponsored agencies	$	19,758	$	(214	)	$	—	$	—		$	19,758	$	(214	)
Mortgage-backed securities-residential		78,982		(382	)		69,142		(568	)		148,124		(950	)
SBA pool securities		—		—			2,784		(15	)		2,784		(15	)
State and political subdivisions		783		(1	)		—		—			783		(1	)
Total	$	99,523	$	(597	)	$	71,926	$	(583	)	$	171,449	$	(1,180	)

Management believes that the unrealized losses on investment securities available for sale are temporary and due to interest rate fluctuations and/or volatile market conditions rather than the credit worthiness of the issuers. The Company does not intend to sell these securities nor is it likely that it will be required to sell the securities before their anticipated recovery; therefore, none of the securities in an unrealized loss position were determined to be other-than-temporarily impaired.

No other-than-temporary impairment charges were recognized in 2020, 2019 or 2018.

The Company has an investment in a CRA investment fund with a fair value of $15.1 million and $10.8 million at December 31, 2020 and 2019, respectively. The investment is classified as an equity security in our Consolidated Statements of Condition. During the first quarter of 2018, the Company adopted ASU 2016-01 “Financial Instruments” which resulted in the reclassification of the Company’s investment in the CRA investment fund from available for sale to equity securities, which resulted in gains of $281,000 and $117,000 for the years ended December 31, 2020 and 2019, respectively, and a loss of $105,000 for the year ended December 31, 2018. This amount is included in securities gains/(losses), net on the Consolidated Statements of Income.