Interest income on securities decreased $74,000, or 14.3%, to $443,000 for the three months ended March 31, 2020 from $517,000 for the three months ended March 31, 2019 due to a $14.0 million decrease in the average balance of securities to $66.7 million for the three months ended March 31, 2020 from $80.7 million for the three months ended March 31, 2019 and a 44 basis point decrease in the average yield from 7.11% for the three months ended March 31, 2019 to 6.89% for the three months ended March 31, 2020.
Interest Expense. Interest expense decreased $42,000, or 1.5%, to $2.8 million for the three months ended March 31, 2020 from $2.9 million for the three months ended March 31, 2019. The decrease primarily reflected a 1 basis point decrease in the average cost of interest-bearing liabilities to 2.00% for the three months ended March 31, 2020 from 2.01% for the three months ended March 31, 2019, as well as a $5.0 million decrease in the average balance of interest-bearing liabilities.
Interest expense on interest-bearing deposits decreased $118,000, or 4.9%, to $2.3 million for the three months ended March 31, 2020 from $2.4 million for the three months ended March 31, 2019. This decrease was due primarily to a $32.8 million decrease in the average balance of deposits to $470.4 million for the three months ended March 31, 2020 from $503.2 million for the three months ended March 31, 2019, offset by four basis point increase in the average cost of interest-bearing deposits to 1.98% for the three months ended March 31, 2020 from 1.94% for the three months ended March 31, 2019 and. The increase in the average cost of deposits was due to the rising costs of retaining deposits in a competitive environment and a higher percentage of certificates of deposit relative to total deposits. The decrease in the average balance of deposits was primarily due to the decrease in the average balance of NOW and money market accounts.
Interest expense on Federal Home Loan Bank borrowings increased $75,000, or 17.1%, from $442,000 for the three months ended March 31, 2019 to $517,000 for the three months ended March 31, 2020. The increase was primarily due to a $27.9 million increase in the average balance of Federal Home Loan Bank borrowings from $69.2 million for the three months ended March 31, 2019 to $97.0 million for the three months ended March 31, 2020. This interest increase was offset by a 42 basis point decrease in the average cost of Federal Home Loan Bank borrowings from 2.56% for the three months ended March 31, 2019 to 2.14% for the three months ended March 31, 2020.
Net Interest Income. Net interest income increased $269,000, or 9.6%, to $3.1 million for the three months ended March 31, 2020 from $2.8 million for the three months ended March 31, 2019. The decrease reflected a 14 basis point decrease in our net interest rate spread to 1.42% for the three months ended March 31, 2020 from 1.56% for the three months ended March 31, 2019. Our net interest margin increased 2 basis points to 1.79% for the three months ended March 31, 2020 from 1.77% for the three months ended March 31, 2019.
Provision for Loan Losses. We recorded a provision for loan losses of $25,000 for the three months ended March 31, 2020 and we recorded no provision for loan losses for the three-month period ended March 31, 2019. Higher loan balances were the reason for the provision during the three months ended March 31, 2020. The Bank continues to have a low level of delinquent andnon-accrual loans in the portfolio, as well as no charge-offs.Non-performing assets decreased to $587,000, or 0.08% of total assets, at March 31, 2020. We recorded no net charge-offs for the three months ended March 31, 2020 compared to $40,000 in recovery for the three months ended March 31, 2019. The allowance for loan losses was $2.0 million, or 0.37% of loans outstanding, at March 31, 2020.
Non-Interest Income.Non-interest income decreased $19,000, or 13.5%, to $121,000 for the three months ended March 31, 2020 from $140,000 for the three months ended March 31, 2019 due to a $10,000 decrease in collection of mortgage late fees and a $9,000 decrease in othernon-interest income, which included less loan servicing income.
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