Note 2 — Securities

The following is a summary of securities available for sale as of the dates indicated:

The amortized cost and estimated fair value of securities as of March 31, 2020, by contractual or expected maturity, are shown below. Collateralized mortgage obligations are included in the table shown below based on their expected maturities. All other securities are included based on their contractual maturities.

CECL (ASU 2016-13) requires the Company to assess its available-for-sales securities portfolio for impairment on an at least quarterly basis.  The Company performed an impairment assessment of the Bank’s investment in debt securities in accordance with this standard.  This assessment took into account the credit quality of these debt securities and determined that since all were U.S. Treasury obligations, U.S. government agency securities, and U.S. government sponsored agency securities, they all have the backing of the U.S. government, and thus no credit impairment is expected.

Gross unrealized losses on securities available for sale, the estimated fair value of the related securities and the number of securities aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows as of March 31, 2020 and December 31, 2019:

The unrealized losses in the U.S. government agency and sponsored agency obligations, as it relates to mortgage-backed securities and in the collateralized mortgage obligation securities were caused by fluctuations in interest rates. These securities are not deemed to have credit risk due to their long history with no credit losses, and the explicit guarantee of the U.S. government of timely payment of principal and interest to investors. The Company does not intend to sell the securities and it is not more likely than not that it will be required to sell them before recovery of their amortized cost.

Realized gains and losses on sales of securities and proceeds from sales of securities were as follows for the periods indicated:

During the three months ended March 31, 2020, there were no securities sales transactions. During the three months ended March 31, 2019, there was $725,000 in net gains in earnings resulting from the sale of securities. A net unrealized loss of $206,000 related to these securities had previously been recorded in accumulated other comprehensive income as of the beginning of the period in 2019. 

Securities available for sale with market values of $52.7 million and $30.0 million as of March 31, 2020 and 2019, respectively, were pledged to secure public deposits and for other purposes as required or permitted by law.