NOTE 4: SECURITIES

The following table provides a summary of the Company’s AFS securities portfolio at December 31:

		Amortized Cost		Gross Unrealized					Estimated Fair Value
(dollars in thousands)		Amortized Cost		Gains		Losses			Estimated Fair Value
2017:
US Treasury securities	$	499	$	—	$	(6	)	$	493
Agency mortgage-backed securities		471,131		287		(7,399	)		464,019
Beneficial interest – FHLMC securitization		35,930		1,811		(1,889	)		35,852
Corporate bonds		19,000		—		—			19,000
Total	$	526,560	$	2,098	$	(9,294	)	$	519,364
2016:
US Treasury securities	$	300	$	—	$	(3	)	$	297
Agency mortgage-backed securities		476,163		160		(7,414	)		468,909
Beneficial interest – FHLMC securitization		42,028		711		(2,367	)		40,372
Total	$	518,491	$	871	$	(9,784	)	$	509,578

The US Treasury Securities are pledged as collateral to the State of California to meet regulatory requirements related to the Bank’s trust operations.

The table below indicates, as of December 31, 2017, the gross unrealized losses and fair values of our investments, aggregated by investment category and length of time that the individual securities have been in a continuous unrealized loss position.

	Securities with Unrealized Loss at December 31, 2017
(dollars in thousands)	Less than 12 months					12 months or more					Total
(dollars in thousands)	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
US Treasury securities	$	197	$	(2	)	$	296	$	(4	)	$	493	$	(6	)
Agency mortgage backed securities		158,984		(1,394	)		259,213		(6,005	)		418,197		(7,399	)
Beneficial interest – FHLMC securitization		—		—			8,738		(1,889	)		8,738		(1,889	)
Total temporarily impaired securities	$	159,181	$	(1,396	)	$	268,247	$	(7,898	)	$	427,428	$	(9,294	)

	Securities with Unrealized Loss at December 31, 2016
(dollars in thousands)	Less than 12 months					12 months or more				Total
(dollars in thousands)	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
US Treasury securities		297		(3	)		—		—		297		(3	)
Agency mortgage backed securities		445,591		(7,414	)		—		—		445,591		(7,414	)
Beneficial interest – FHLMC securitization		18,636		(2,367	)		—		—		18,636		(2,367	)
Total temporarily impaired securities	$	464,524	$	(9,784	)	$	—	$	—	$	464,524	$	(9,784	)

Unrealized losses on US Treasury securities, agency notes and agency mortgage-backed securities have not been recognized into income because the issuer bonds are of high credit quality, management does not intend to sell and it is not more likely than not that management would be required to sell the securities prior to their anticipated recovery. The decline in fair value is largely due to changes in interest rates. The fair value is expected to recover as the bonds approach maturity.

The scheduled maturities of securities AFS, other than agency mortgage backed securities, and the related weighted average yield is as follows as of December 31:

(dollars in thousands)	Less than 1 Year			1 Through 5 years			5 Through 10 Years			After 10 Years			Total
2017
Amortized Cost:
US Treasury securities	$	—		$	499		$	—		$	—		$	499
Corporate bonds		—			—			19,000			—			19,000
Total		—			499			19,000			—			19,499
Weighted average yield		—	%		1.03	%		5.24	%		—	%		5.13	%
Estimated Fair Value:
US Treasury securities	$	—		$	493		$	—		$	—		$	493
Corporate bonds		—			—			19,000			—			19,000
Total	$	—		$	493		$	19,000		$	—		$	19,493

(dollars in thousands)	Less than 1 Year			1 Through 5 years			5 Through 10 Years			After 10 Years			Total
2016
Amortized Cost:
US Treasury securities	$	—		$	300		$	—		$	—		$	300
Weighted average yield		—	%		0.90	%		—	%		—	%		0.90	%
Estimated Fair Value:
US Treasury securities	$	—		$	297		$	—		$	—		$	297
Total	$	—		$	297		$	—		$	—		$	297

Agency mortgage backed securities and beneficial interests in FHLMC securitizations are excluded from the above table because such securities are not due at a single maturity date. The weighted average yield of the agency mortgage backed securities and beneficial interests in FHLMC securitizations as of December 31, 2017 and 2016 was 2.55% and 2.58%, respectively.