Investment Securities

The carrying values and estimated fair values of investment securities at the periods indicated are presented below:



(In Thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
June 30, 2018
Securities available for sale
U.S. Treasury and government sponsored entities		$210,973		$13		$2,294		$208,692
Municipal securities	11,938		22		25		11,935
Corporate bonds	37,143		358		11		37,490
Collateralized loan obligations	6,001		7		1		6,007
Total securities available for sale		$266,055		$400		$2,331		$264,124
December 31, 2017
Securities available for sale
U.S. Treasury and government sponsored entities		$250,794		$3		$1,336		$249,461
Municipal securities	14,395		72		46		14,421
Corporate bonds	36,654		478		—		37,132
Collateralized loan obligations	6,000		5		—		6,005
Total securities available for sale		$307,843		$558		$1,382		$307,019

Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at June 30, 2018 and December 31, 2017 were as follows:



	Less Than 12 Months				More Than 12 Months				Total
(In Thousands)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
June 30, 2018:
Securities Available for Sale
U.S. Treasury and government sponsored entities		$101,236		$1,495		$102,446		$799		$203,682		$2,294
Corporate bonds	4,008		11		—		—		4,008		11
Collateralized loan obligations	2,999		1		—		—		2,999		1
Municipal securities	2,907		7		1,361		18		4,268		25
Total		$111,150		$1,514		$103,807		$817		$214,957		$2,331

December 31, 2017:
Securities Available for Sale
U.S. Treasury and government sponsored entities		$116,331		$496		$122,605		$840		$238,936		$1,336
Municipal securities	3,994		17		2,298		29		6,292		46
Total		$120,325		$513		$124,903		$869		$245,228		$1,382

The unrealized losses on investments in U.S. treasury and government sponsored entities, corporate bonds, collateralized loan obligations, and municipal securities in both periods were caused by changes in interest rates. At June 30, 2018 and December 31, 2017, there were 24 available-for-sale securities with unrealized losses that have been in a loss position for less than twelve months. There were 17 securities as of June 30, 2018 and December 31, 2017 that have been in an unrealized loss position for more than twelve months. The contractual terms of the investments in a loss position do not permit the issuer to settle the securities at a price less than the amortized cost of the investment. Because it is more likely than not that the Company will hold these investments until a market price recovery or maturity, these investments are not considered other-than-temporarily impaired.

At June 30, 2018 and December 31, 2017, $53.6 million and $51.6 million in securities were pledged for deposits and borrowings, respectively.

The amortized cost and estimated fair values of debt securities and preferred stock at June 30, 2018, are distributed by contractual maturity as shown below. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Although preferred stock has no stated maturity, it is aggregated in the calculation of weighted average yields presented below in the category of investments that mature in ten years or more.



(In Thousands)	Amortized Cost		Fair Value		Weighted Average Yield
US Treasury and government sponsored entities
Within 1 year		$52,510		$52,396	1.08	%
1-5 years	155,133		152,981		1.76	%
5-10 years	3,330		3,315		3.00	%
Total		$210,973		$208,692	1.61	%
Corporate bonds
1-5 years		$21,700		$21,904	3.20	%
5-10 years	15,443		15,586		3.44	%
Total		$37,143		$37,490	3.30	%
Collateralized loan obligations
5-10 years		$3,000		$2,999	3.81	%
Over 10 years	3,001		3,008		4.11	%
Total		$6,001		$6,007	3.96	%
Preferred stock
Over 10 years		$5,868		$6,006	5.77	%
Total		$5,868		$6,006	5.77	%
Municipal securities
Within 1 year		$2,607		$2,606	1.32	%
1-5 years	9,331		9,329		2.42	%
Total		$11,938		$11,935	2.18	%

The proceeds and resulting gains and losses, computed using specific identification, from sales of investment securities for the three and six month periods ending June 30, 2018 and 2017, are as follows:



(In Thousands)	Proceeds		Gross Gains		Gross Losses
Three Months Ended June 30, 2018
Available for sale securities		$—		$—		$—
Three Months Ended June 30, 2017
Available for sale securities		$—		$—		$—
Six Months Ended June 30, 2018
Available for sale securities		$—		$—		$—
Six Months Ended June 30, 2017
Available for sale securities		$10,010		$14		$—

A summary of interest and dividend income for the three and six month periods ending June 30, 2018 and 2017, on available for sale investment securities and marketable equity securities are as follows:



	Three Months Ended June 30,				Six Months Ended June 30,
(In Thousands)	2018		2017		2018		2017
US Treasury and government sponsored entities		$895		$824		$1,785		$1,602
Other	427		294		787		583
Total taxable interest income		$1,322		$1,118		$2,572		$2,185
Municipal securities		$64		$92		$150		$189
Total tax-exempt interest income		$64		$92		$150		$189
Total		$1,386		$1,210		$2,722		$2,374