Program Liquidity Facility (βPPPLFβ) borrowings. Under the PPPLF, the Bank pledged PPP loans at face value as collateral to obtain Federal Reserve Bank (βFRBβ) non-recourse loans. The increase from the prior year is primarily due to the PPPLF and Federal Home Loan Bank (βFHLBβ) borrowings.
Total stockholdersβ equity increased $9.5 million, to $230.0 million at December 31, 2020, from $220.6 million at SeptemberΒ 30, 2020, and increased $29.8 million, from $200.2 million at December 31, 2019. The increase in stockholdersβ equity during the current quarter was primarily due to net income of $11.4 million, partially offset by the common stock repurchases of $1.1 million, and $752,000 of other comprehensive loss, net of tax. The Company repurchased 25,135 shares of its common stock during the quarter ended December 31, 2020, at an average price of $44.78 per share. Book value per common share was $55.33 at December 31, 2020, compared to $52.82 at September 30, 2020, and $45.85 at December 31, 2019.
The Bank is well capitalized under the minimum capital requirements established by the Federal Deposit Insurance Corporation (βFDICβ) at December 31, 2020 with a CBLR of 10.9%, compared to the normally required CBLR of greater than 9.0% and the regulatory approved reduced CBLR of 8.0% due to the COVID-19 pandemic. Beginning in 2021, the CBLR will increase to 8.5% for the calendar year. The Companyβs Tier 1 leverage capital ratio was 11.1% at December 31, 2020.
Credit Quality
The ALLL at December 31, 2020, increased to $26.2 million, or 1.66% of gross loans receivable, excluding loans HFS, compared to $24.8 million, or 1.63% of gross loans receivable, excluding loans HFS at September 30, 2020, and $13.2 million, or 0.98% of gross loans receivable, excluding loans HFS, at December 31, 2019. The adjusted ALLL to gross loans receivable, excluding loans HFS and PPP loans, was 1.73% at December 31, 2020 (See βNon-GAAP Financial Measuresβ). Non-performing loans increased to $7.8 million at December 31, 2020, from $7.6 million at September 30, 2020 and increased from $3.0 million at December 31, 2019. The increase in non-performing loans quarter over linked quarter was primarily a result of $1.3 million in additional nonperforming commercial business loans, offset by one commercial real estate loan in the amount of $1.1 million returned to active status , and the year over year increase was associated with borrowers adversely impacted by the COVID-19 pandemic, primarily in the commercial business sector.
Loans classified as substandard decreased $809,000 to $17.6 million at December 31, 2020, compared to $18.5 million at September 30, 2020, and increased $10.9 million from $6.7 million at December 31, 2019. The quarter over linked quarter decrease in substandard loans was attributable to a commercial real estate loan of $1.0 million returning to performing status, partially offset by additional consumer loans. The year over year increase in substandard loans was primarily due to one relationship with mortgage loans totaling $4.5 million, one relationship with mortgage, commercial real estate, and commercial business loans totaling $3.3 million, and two commercial business loans totaling $4.4 million. There was one other real estate owned (βOREOβ) property of $90,000 at both December 31, 2020 and September 30, 2020, compared to two OREO properties totaling $168,000 at December 31, 2019.
Included in the carrying value of gross loans are net discounts on loans purchased in the Anchor Bank acquisition in November 2018. The remaining net discount on loans acquired was $1.5 million, $1.8 million, and $2.7 million, on $132.6 million, $159.2 million, and $198.5 million of gross loans at December 31, 2020, September 30, 2020, and December 31, 2019, respectively.
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