Results of Operations for the Years Ended December 31, 2021 and 2020
General. Net income increased $5.3 million or 42.1%, to $17.9 million for the year ended December 31, 2021 from $12.6 million for the year ended December 31, 2020. The increase resulted from a $6.4 million increase in noninterest income and a $6.3 million increase in net interest income, partially offset by an increase in noninterest expense of $6.4 million.
Net Interest Income. Net interest income increased $6.3 million, or 16.7%, to $43.7 million for the year ended December 31, 2021 from $37.4 million for the year ended December 31, 2020, due to a $5.9 million net increase in interest income and a $362 thousand decrease in interest expense.
Our net interest margin increased 2 basis points to 4.49% for the year ended December 31, 2021 from 4.47% for the year ended December 31, 2020. The increase in net interest margin was due to a 9 basis point decrease in the cost of interest bearing deposits, offset by the decrease in interest earning asset yields of 3 basis points, primarily due to the historically low interest rate environment. Our asset and liability management model allows us to maintain our net interest margin at this level as the growth in our interest earning assets was primarily funded by a $114.3 million, or 37.9%, increase in average noninterest bearing demand deposits to $415.7 million for the year ended December 31, 2021 from $301.4 million for the year ended December 31, 2020.
Interest Income. Interest income increased $5.9 million or 15.3%, to $44.5 million for the year ended December 31, 2021 from $38.6 million for the year ended December 31, 2020 and was attributable to an increase in loan and reverse repurchase interest income offset by a decrease in interest income on securities and interest earning cash and other.
Loan interest income increased $6.0 million, or 16.7%, to $41.5 million for the year ended December 31, 2021 from $35.6 million for the year ended December 31, 2020. This increase was attributable to a $112.4 million, or 18.6%, increase in the average loan balance from our litigation-related and multifamily loan portfolios offset by a 9 basis point decrease in loan yields. The decrease in loan yields is primarily due to the impact of the historically low interest rate environment and its effect on our real estate loan portfolio pricing. The impact of the decline in loan yields on interest income was primarily offset by a 9 basis point decrease in rates on interest bearing deposits as part of the Company’s overall asset/liability management strategy.
Securities interest income decreased $382 thousand, or 14.9%, to $2.2 million for the year ended December 31, 2021 from $2.6 million for the year ended December 31, 2020. This decrease was attributable to a 41 basis point decrease in yields, driven by accelerated prepayments due to the current interest rate environment, offset by a $7.8 million, or 6.2%, increase in average securities balances at a lower rate.
Securities purchased under agreements to resell interest income increased $525 thousand to $619 thousand for the year ended December 31, 2021 from $94 thousand for the year ended December 31, 2020 as this program commenced in the fourth quarter of 2020.
Interest earning cash and other interest income decreased $199 thousand, or 50.8%, to $193 thousand for the year ended December 31, 2021 from $392 thousand for the year ended December 31, 2020. This decrease was attributable to a 12 basis point decrease in yields driven by the current interest rate environment as well as a $28.9 million, or 29.2%, decrease in average cash balance primarily due to the investment of cash into higher yielding loans.
Interest Expense. Interest expense decreased $362 thousand, or 30.4%, to $828 thousand for the year ended December 31, 2021 from $1.2 million for the year ended December 31, 2020, primarily attributable to rate reductions on deposits. Interest rates we paid on interest bearing deposits decreased 9 basis points to 0.18% for the year ended December 31, 2021 from 0.27% for the year ended December 31, 2020. Our average balance of interest bearing deposits increased $12.6 million, or 2.9%, to $450.9 million for the year ended December 31, 2021 from $438.3 million for the year ended December 31, 2020 attributable primarily to litigation related deposit growth.
Provision for Loan Losses. Our provision for loan losses was $7.0 million for the year ended December 31, 2021 compared to $6.3 million for the year ended December 31, 2020. The 2021 provision included approximately $5.1 million