Debt securities have been classified as available-for-sale or held-to-maturity in the consolidated balance sheet according to management’s intent. The following table presents the amortized cost and fair value of the investment securities as of the dates indicated:



($ in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
December 31, 2018
Securities available-for-sale:
U.S. government agency and U.S. government sponsored enterprise securities:
Mortgage-backed securities	$	68,975	$	177	$	(1,231	)	$	67,921
Collateralized mortgage obligations	56,625		55		(1,031		)	55,649
SBA loan pool securities	23,144		—		(512		)	22,632
Municipal bonds	784		5		—			789
Total securities available-for-sale	$	149,528	$	237	$	(2,774	)	$	146,991
Securities held-to-maturity:
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities	$	16,659	$	—	$	(602	)	$	16,057
Municipal bonds	5,101		37		(43		)	5,095
Total securities held-to-maturity	$	21,760	$	37	$	(645	)	$	21,152
December 31, 2017
Securities available-for-sale:
U.S. government agency and U.S. government sponsored enterprise securities:
Mortgage-backed securities	$	52,565	$	8	$	(669	)	$	51,904
Collateralized mortgage obligations	51,459		34		(1,008		)	50,485
SBA loan pool securities	25,231		17		(323		)	24,925
Municipal bonds	2,376		1		(2		)	2,375
Total securities available-for-sale	$	131,631	$	60	$	(2,002	)	$	129,689
Securities held-to-maturity:
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities	$	15,807	$	8	$	(257	)	$	15,558
Municipal bonds	5,263		181		(5		)	5,439
Total securities held-to-maturity	$	21,070	$	189	$	(262	)	$	20,997

As of December 31, 2018 and 2017, pledged securities were $112.2 million and $109.9 million, respectively. These securities were pledged for the State Deposit from the California State Treasurer.

The following table presents the amortized cost and fair value of the investment securities by contractual maturity as of December 31, 2018. 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.



	Securities Available-For-Sale				Securities Held-To-Maturity
($ in thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Within one year	$	—	$	—	$	133	$	133
One to five years	—		—		1,435		1,442
Five to ten years	784		789		1,216		1,217
Greater than ten years	—		—		2,317		2,303
Mortgage-backed securities, collateralized mortgage obligations and SBA loan pool securities	148,744		146,202		16,659		16,057
Total	$	149,528	$	146,991	$	21,760	$	21,152

The following table presents proceeds from sales and calls of securities available-for-sale and the associated gross gains and losses realized through earnings upon the sales and calls of securities available-for-sale for the periods indicated:



	Year Ended December 31,
($ in thousands)	2018		2017		2016
Gross realized gains on sales and calls of securities available-for-sale	$	—	$	—	$	54
Gross realized losses on sales and calls of securities available-for-sale	—		—		46
Net realized gains (losses) on sales and calls of securities available-for-sale	$	—	$	—	$	8
Proceeds from sales and calls of securities available-for-sale	$	1,075	$	—	$	7,816
Tax expense on sales and calls of securities available-for-sale	$	—	$	—	$	3

The following table summarizes the investment securities with unrealized losses by security type and length of time in a continuous unrealized loss position as of the dates indicated:



	Length of Time that individual securities have been in a continuous unrealized loss position
	Less Than 12 Months						12 Months or Longer						Total
($ in thousands)	Fair Value		Gross Unrealized Losses			Number of Securities	Fair Value		Gross Unrealized Losses			Number of Securities	Fair Value		Gross Unrealized Losses			Number of Securities
December 31, 2018
Securities available-for-sale:
U.S. government agency and U.S. government sponsored enterprise securities:
Mortgage-backed securities	$	1,868	$	(6	)	2	$	41,845	$	(1,225	)	48	$	43,713	$	(1,231	)	50
Collateralized mortgage obligations	7,067		(29		)	5	34,943		(1,002		)	34	42,010		(1,031		)	39
SBA loan pool securities	2,809		(7		)	2	19,823		(505		)	18	22,632		(512		)	20
Municipal bonds	—		—			—	—		—			—	—		—			—
Total securities available-for-sale	$	11,744	$	(42	)	9	$	96,611	$	(2,732	)	100	$	108,355	$	(2,774	)	109
Securities held-to-maturity:
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities	$	2,022	$	(23	)	1	$	14,035	$	(579	)	15	$	16,057	$	(602	)	16
Municipal bonds	2,600		(38		)	8	497		(5		)	3	3,097		(43		)	11
Total securities held-to-maturity	$	4,622	$	(61	)	9	$	14,532	$	(584	)	18	$	19,154	$	(645	)	27
December 31, 2017
Securities available-for-sale:
U.S. government agency and U.S. government sponsored enterprise securities:
Mortgage-backed securities	$	31,876	$	(352	)	29	$	18,762	$	(317	)	21	$	50,638	$	(669	)	50
Collateralized mortgage obligations	31,191		(454		)	19	16,284		(554		)	19	47,475		(1,008		)	38
SBA loan pool securities	11,736		(103		)	9	8,798		(220		)	7	20,534		(323		)	16
Municipal bonds	1,115		(2		)	2	—		—			—	1,115		(2		)	2
Total securities available-for-sale	$	75,918	$	(911	)	59	$	43,844	$	(1,091	)	47	$	119,762	$	(2,002	)	106
Securities held-to-maturity:
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities	$	7,997	$	(93	)	6	$	5,739	$	(164	)	7	$	13,736	$	(257	)	13
Municipal bonds	1,183		(5		)	5	—		—			—	1,183		(5		)	5
Total securities held-to-maturity	$	9,180	$	(98	)	11	$	5,739	$	(164	)	7	$	14,919	$	(262	)	18

In accordance with FASB ASC 320, Investments - Debt and Equity Securities, the Company performs an OTTI assessment at least on a quarterly basis. OTTI is recognized when fair value is below the amortized cost where: (i) an entity has the intent to sell the security; (ii) it is more likely than not that an entity will be required to sell the security before recovery of its amortized cost basis; or (iii) an entity does not expect to recover the entire amortized cost basis of the security.

All individual securities in a continuous unrealized loss position for 12 months or more as of December 31, 2018 and 2017 had an investment grade rating upon purchase. The issuers of these securities have not established any cause for default on these securities and various rating agencies have reaffirmed their long-term investment grade status as of December 31, 2018 and 2017. These securities have fluctuated in value since their purchase dates as market interest rates fluctuated. The Company does not intend to sell these securities and it is more likely than not that the Company will not be required to sell before the recovery of its amortized cost basis. In addition, the unrealized losses on municipal bonds are not considered other-than-temporary impaired, as the bonds are rated investment grade and there are no credit quality concerns with the issuers. Interest payments have been made as scheduled, and management believes this will continue in the future until the bonds get paid in full. The Company determined that the investment securities with unrealized losses for twelve months or more are not other-than-temporary impaired, and, therefore, no impairment was recognized during the years ended December 31, 2018, 2017 and 2016.