● book value per common share was $ 8.47 at december 31 , 2018 compared to $ 7.82 at december 31 , 2017. tangible book value per common share ( non-gaap ) which excludes goodwill and core deposit intangibles from shareholders ' equity was $ 8.36 at december 31 , 2018 compared to $ 7.70 at december 31 , 2017. management believes that tangible book value per share is meaningful because it is a measure that the company and investors commonly use to assess capital adequacy . ● average total equity increased by $ 14.3 million ( 12 % ) to $ 130.2 million for the year ended december 31 , 2018 , compared to $ 115.9 million for the year ended december 31 , 2017 . ● the bank maintained capital levels in excess of the “ well-capitalized ” standards for the year ended december 31 , 2018. credit quality ● nonperforming assets at december 31 , 2018 totaled $ 4.2 million or 0.32 % of total assets , a decrease of $ 1.7 million ( 28 % ) since december 31 , 2017 . ● there was no provision for loan and lease losses during the current year as a result of continued improved asset quality and net loan loss recoveries . the company recorded a provision for loan and lease losses of $ 950 thousand during the year ended december 31 , 2017 reflecting growth in the loan portfolio . vision and objectives we seek to provide competitive , long-term returns to our shareholders while serving the financial needs of the communities in our market . management strives to provide those returns while exercising prudent risk management practices and maintaining adequate levels of capital and reserves . our vision is to remain independent , expanding our presence with organic growth and the addition of new strategically important locations . we will pursue attractive opportunities to enter related lines of business and to acquire financial institutions with complementary lines of business when it is beneficial to do so . during 2018 our organic growth in average assets totaled $ 90.6 million or 8 % . our long-term success rests on the shoulders of the leadership team and its ability to effectively enhance the performance of the company . as a financial services company , we are in the business of taking and managing risks . whether we are successful depends largely upon whether we take the right risks and are rewarded appropriately for those risks . our governance structure enables us to manage all major aspects of our business effectively through an integrated process that includes financial , strategic , risk and leadership planning . we define risks to include not only credit , market and liquidity risk , the traditional concerns for financial institutions , but also operational risks , including risks related to systems , processes or external events , as well as legal , regulatory and reputation risks . our management processes , structures , and policies help to ensure compliance with laws and regulations and provide clear lines for decision-making and accountability . results are important , but equally important is how we achieve those results . our core values and commitment to high ethical standards are essential to maintaining and to sustaining public trust and confidence in our company . sources of income we derive our income primarily from net interest income , which is the difference between the interest income we receive on interest-earning assets and the interest expense we pay on interest-bearing liabilities . net interest income is impacted by many factors that are beyond our control , including general economic conditions and the policies of various governmental and regulatory agencies , the federal reserve board in particular . in recent years , we originated higher volumes of longer term fixed rate loans . these loans , combined with the structure of our investment portfolio , the use of floors in the pricing of our variable rate loans and funding mix caused the company to become neutral to slightly to moderately liability sensitive , which could negatively impact earnings in a rapidly rising interest rate environment . 22 bank of commerce holdings & subsidiaries net interest income reflects both the amount of earning assets we hold and our net interest margin , which is the difference between the yields we receive on our earning assets and the interest rates we pay to fund those assets . as a result , changes in either our net interest margin or the amount of earning assets we hold will affect our net interest income and earnings . increases or decreases in interest rates could adversely affect our net interest margin . although our asset yields and funding costs tend to move in the same direction in response to changes in interest rates , one can rise or fall faster than the other , and cause our net interest margin to expand or contract . many of our assets are tied to indexes , which adjust in response to changes in interest rates . changes in the slope of the yield curve , and the spread between short-term and long-term interest rates could also reduce our net interest margin . normally , the yield curve is upward sloping , which means that short-term rates are lower than long-term rates . because our liabilities tend to be shorter in duration than our assets , when the yield curve flattens or even inverts , we could experience pressure on our net interest margin as our cost of funds increases relative to the yield we can earn on our assets . we assess our interest rate risk by estimating the effect of interest rate changes on our earnings under various simulated scenarios . the scenarios differ based on assumptions including the direction , magnitude and speed of interest rate changes , and the slope of the yield curve . story_separator_special_tag available-for-sale investment securities totaled $ 257.0 million at december 31 , 2018 , compared with $ 266.9 million at december 31 , 2017. our available-for-sale investment portfolio provides a secondary source of liquidity to fund other higher yielding asset opportunities , such as loan originations and wholesale loan purchases . during 2018 , we purchased 37 securities with a par value of $ 57.1 million and weighted average yield of 3.40 % and sold 45 securities with a par value of $ 29.7 million and weighted average yield of 2.51 % . the sales and call activity on securities resulted in $ 43.7 thousand in net realized gains for the year ended december 31 , 2018. during 2018 we also received $ 31.5 million in proceeds from principal payments , calls and maturities within the portfolio . at december 31 , 2018 , our net unrealized losses on available-for-sale securities were $ 4.3 million compared with $ 452 thousand net unrealized losses at december 31 , 2017. the changes in the net unrealized losses on the investment securities portfolio are primarily due to changes in market interest rates . we recorded gross loan balances of $ 946.3 million at december 31 , 2018 , compared with $ 879.8 million at december 31 , 2017 , an increase of $ 66.4 million . the increase in gross loans occurred primarily in the bank 's sacramento marketplace and is the result of past investments in our sba division and in our expanded sacramento commercial banking group . the alll at december 31 , 2018 increased $ 367 thousand to $ 12.3 million compared to $ 11.9 million at december 31 , 2017. as a result of continued improved asset quality , and net loan loss recoveries , no provision for loan and lease losses was necessary during the year ended december 31 , 2018. a provision for loan and lease losses of $ 950 thousand was recorded during the year ended december 31 , 2017. net loan loss recoveries were $ 367 thousand during the year ended december 31 , 2018 , compared with net loan charge-offs of $ 569 thousand during the prior year . at december 31 , 2018 , relying on our alll methodology , which uses criteria such as risk factors and historical loss rates , and given the ongoing improvements in asset quality , we believe the alll is adequate . there is , however , no assurance that future loan and lease losses will not exceed the levels provided for in the alll and could possibly result in additional charges to the provision for loan and lease losses . nonperforming loans , which include nonaccrual loans and accruing loans past due over 90 days , decreased by $ 1.7 million to $ 4.1 million , or 0.44 % of gross loans , as of december 31 , 2018 , compared to $ 5.8 million , or 0.66 % of gross loans as of december 31 , 2017. the decrease in nonperforming loans was primarily due to repayments totaling $ 1.2 million from one commercial loan and one commercial real estate loan . past due loans as of december 31 , 2018 increased to $ 13.9 million , compared to $ 2.3 million as of december 31 , 2017. the increase in past due loans was primarily due to three commercial real estate loans totaling $ 12.1 million . we believe that risk grading for past due and nonperforming loans appropriately reflects the risk associated with the past due loans . see note 5 loans in the notes to consolidated financial statements in this document for further detail on the alll and the loan portfolio . premises and equipment totaled $ 13.1 million at december 31 , 2018 , a decrease of $ 1.6 million compared to $ 14.7 million at december 31 , 2017. the decrease was primarily due to provision for depreciation and amortization recognized during the current year . our oreo balance at december 31 , 2018 was $ 31 thousand compared to $ 35 thousand at december 31 , 2017. for the year ended december 31 , 2018 , we transferred five foreclosed properties in the amount of $ 140 thousand to oreo . during 2018 , we sold five properties with balances of $ 144 thousand for a net gain of $ 73 thousand . see note 8 , other real estate owned in the notes to consolidated financial statements in this document , for further details relating to our oreo portfolio . bank-owned life insurance increased $ 512 thousand during the year ended december 31 , 2018 to $ 22.4 million compared to $ 21.9 million at december 31 , 2017. our net deferred tax assets were $ 7.0 million at december 31 , 2018 compared to $ 6.5 million at december 31 , 2017. other assets which include the bank 's investment in qualified zone academy bonds , federal home loan bank of san francisco stock and low income housing tax credit partnerships totaled $ 22.5 million at december 31 , 2018 compared to $ 21.3 million at december 31 , 2017. total deposits at december 31 , 2018 , increased $ 29 million or 3 % to $ 1.132 billion compared to december 31 , 2017 . ● total non-maturing deposits increased $ 65.9 million or 7 % compared to the same date a year ago . ● certificates of deposit decreased $ 36.9 million or 19 % compared to the same date a year ago . other liabilities which include the bank 's supplemental executive retirement plan and funding obligation for investments in qualified affordable housing partnerships increased $ 563 thousand to $ 13.4 million as of december 31 , 2018 compared to $ 12.8 million at december 31 , 2017 . 29 bank of commerce holdings & subsidiaries investment securities the composition of our investment securities portfolio reflects management 's investment strategy of maintaining an appropriate level

capital resources we use equity capital to support growth and pay dividends . the objective of effective capital management is to produce above market long-term returns for our shareholders . our sources of capital include retained earnings , common and preferred stock issuance , and issuance of subordinated debt or trust notes . regulatory capital guidelines federal bank regulatory agencies use capital adequacy guidelines in the examination and regulation of bank holding companies and banks . the guidelines are “ risk-based , ” meaning that they are designed to make capital requirements more sensitive to differences in risk profiles among banks and bank holding companies . on july 2 , 2013 , the federal banking agencies approved the final rules ( the “ final rules ” ) implementing the basel committee 's december 2010 final capital framework ( commonly known as basel iii ) . the final rules substantially amended the regulatory risk-based capital rules applicable to the holding company and the bank . the phase-in period for the final rules ended january 1 , 2019. generally speaking , the final rules did the following : ● created “ common equity tier 1 capital ratio , ” which is a measure of regulatory capital closer to pure tangible common equity than the previous tier 1 definition ; ● established a required minimum risk-based capital ratio for “ common equity tier 1 capital ratio ” at 4.5 % ; ● increased the required minimum risk-based “ tier 1 capital ratio ” to 6.0 % : ● increased the required minimum risk-based “ total capital ratio ” to 8.0 % ; ● increased the required minimum “ tier 1 leverage ratio ” to 4.0 % ; ● added a 2.50 % capital conversation buffer to the minimum “ common equity tier 1 capital ratio ” , “ tier 1 capital ratio ” and “ total capital ratio ” ; and ● allowed for permanent grandfathering of non-qualifying instruments , such as our trust-preferred securities , subject to a limit of 25 % of tier 1 capital .


 Write a concise suspicious activity report of the following text delimited by triple backquotes. Return your response as a formal report which covers the key points highlighting the location,dates,entity names and account holder information in chronological order of the text.
     ```capital resources we use equity capital to support growth and pay dividends . the objective of effective capital management is to produce above market long-term returns for our shareholders . our sources of capital include retained earnings , common and preferred stock issuance , and issuance of subordinated debt or trust notes . regulatory capital guidelines federal bank regulatory agencies use capital adequacy guidelines in the examination and regulation of bank holding companies and banks . the guidelines are “ risk-based , ” meaning that they are designed to make capital requirements more sensitive to differences in risk profiles among banks and bank holding companies . on july 2 , 2013 , the federal banking agencies approved the final rules ( the “ final rules ” ) implementing the basel committee 's december 2010 final capital framework ( commonly known as basel iii ) . the final rules substantially amended the regulatory risk-based capital rules applicable to the holding company and the bank . the phase-in period for the final rules ended january 1 , 2019. generally speaking , the final rules did the following : ● created “ common equity tier 1 capital ratio , ” which is a measure of regulatory capital closer to pure tangible common equity than the previous tier 1 definition ; ● established a required minimum risk-based capital ratio for “ common equity tier 1 capital ratio ” at 4.5 % ; ● increased the required minimum risk-based “ tier 1 capital ratio ” to 6.0 % : ● increased the required minimum risk-based “ total capital ratio ” to 8.0 % ; ● increased the required minimum “ tier 1 leverage ratio ” to 4.0 % ; ● added a 2.50 % capital conversation buffer to the minimum “ common equity tier 1 capital ratio ” , “ tier 1 capital ratio ” and “ total capital ratio ” ; and ● allowed for permanent grandfathering of non-qualifying instruments , such as our trust-preferred securities , subject to a limit of 25 % of tier 1 capital .
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 Suspicious Activity Report : ● book value per common share was $ 8.47 at december 31 , 2018 compared to $ 7.82 at december 31 , 2017. tangible book value per common share ( non-gaap ) which excludes goodwill and core deposit intangibles from shareholders ' equity was $ 8.36 at december 31 , 2018 compared to $ 7.70 at december 31 , 2017. management believes that tangible book value per share is meaningful because it is a measure that the company and investors commonly use to assess capital adequacy . ● average total equity increased by $ 14.3 million ( 12 % ) to $ 130.2 million for the year ended december 31 , 2018 , compared to $ 115.9 million for the year ended december 31 , 2017 . ● the bank maintained capital levels in excess of the “ well-capitalized ” standards for the year ended december 31 , 2018. credit quality ● nonperforming assets at december 31 , 2018 totaled $ 4.2 million or 0.32 % of total assets , a decrease of $ 1.7 million ( 28 % ) since december 31 , 2017 . ● there was no provision for loan and lease losses during the current year as a result of continued improved asset quality and net loan loss recoveries . the company recorded a provision for loan and lease losses of $ 950 thousand during the year ended december 31 , 2017 reflecting growth in the loan portfolio . vision and objectives we seek to provide competitive , long-term returns to our shareholders while serving the financial needs of the communities in our market . management strives to provide those returns while exercising prudent risk management practices and maintaining adequate levels of capital and reserves . our vision is to remain independent , expanding our presence with organic growth and the addition of new strategically important locations . we will pursue attractive opportunities to enter related lines of business and to acquire financial institutions with complementary lines of business when it is beneficial to do so . during 2018 our organic growth in average assets totaled $ 90.6 million or 8 % . our long-term success rests on the shoulders of the leadership team and its ability to effectively enhance the performance of the company . as a financial services company , we are in the business of taking and managing risks . whether we are successful depends largely upon whether we take the right risks and are rewarded appropriately for those risks . our governance structure enables us to manage all major aspects of our business effectively through an integrated process that includes financial , strategic , risk and leadership planning . we define risks to include not only credit , market and liquidity risk , the traditional concerns for financial institutions , but also operational risks , including risks related to systems , processes or external events , as well as legal , regulatory and reputation risks . our management processes , structures , and policies help to ensure compliance with laws and regulations and provide clear lines for decision-making and accountability . results are important , but equally important is how we achieve those results . our core values and commitment to high ethical standards are essential to maintaining and to sustaining public trust and confidence in our company . sources of income we derive our income primarily from net interest income , which is the difference between the interest income we receive on interest-earning assets and the interest expense we pay on interest-bearing liabilities . net interest income is impacted by many factors that are beyond our control , including general economic conditions and the policies of various governmental and regulatory agencies , the federal reserve board in particular . in recent years , we originated higher volumes of longer term fixed rate loans . these loans , combined with the structure of our investment portfolio , the use of floors in the pricing of our variable rate loans and funding mix caused the company to become neutral to slightly to moderately liability sensitive , which could negatively impact earnings in a rapidly rising interest rate environment . 22 bank of commerce holdings & subsidiaries net interest income reflects both the amount of earning assets we hold and our net interest margin , which is the difference between the yields we receive on our earning assets and the interest rates we pay to fund those assets . as a result , changes in either our net interest margin or the amount of earning assets we hold will affect our net interest income and earnings . increases or decreases in interest rates could adversely affect our net interest margin . although our asset yields and funding costs tend to move in the same direction in response to changes in interest rates , one can rise or fall faster than the other , and cause our net interest margin to expand or contract . many of our assets are tied to indexes , which adjust in response to changes in interest rates . changes in the slope of the yield curve , and the spread between short-term and long-term interest rates could also reduce our net interest margin . normally , the yield curve is upward sloping , which means that short-term rates are lower than long-term rates . because our liabilities tend to be shorter in duration than our assets , when the yield curve flattens or even inverts , we could experience pressure on our net interest margin as our cost of funds increases relative to the yield we can earn on our assets . we assess our interest rate risk by estimating the effect of interest rate changes on our earnings under various simulated scenarios . the scenarios differ based on assumptions including the direction , magnitude and speed of interest rate changes , and the slope of the yield curve . story_separator_special_tag available-for-sale investment securities totaled $ 257.0 million at december 31 , 2018 , compared with $ 266.9 million at december 31 , 2017. our available-for-sale investment portfolio provides a secondary source of liquidity to fund other higher yielding asset opportunities , such as loan originations and wholesale loan purchases . during 2018 , we purchased 37 securities with a par value of $ 57.1 million and weighted average yield of 3.40 % and sold 45 securities with a par value of $ 29.7 million and weighted average yield of 2.51 % . the sales and call activity on securities resulted in $ 43.7 thousand in net realized gains for the year ended december 31 , 2018. during 2018 we also received $ 31.5 million in proceeds from principal payments , calls and maturities within the portfolio . at december 31 , 2018 , our net unrealized losses on available-for-sale securities were $ 4.3 million compared with $ 452 thousand net unrealized losses at december 31 , 2017. the changes in the net unrealized losses on the investment securities portfolio are primarily due to changes in market interest rates . we recorded gross loan balances of $ 946.3 million at december 31 , 2018 , compared with $ 879.8 million at december 31 , 2017 , an increase of $ 66.4 million . the increase in gross loans occurred primarily in the bank 's sacramento marketplace and is the result of past investments in our sba division and in our expanded sacramento commercial banking group . the alll at december 31 , 2018 increased $ 367 thousand to $ 12.3 million compared to $ 11.9 million at december 31 , 2017. as a result of continued improved asset quality , and net loan loss recoveries , no provision for loan and lease losses was necessary during the year ended december 31 , 2018. a provision for loan and lease losses of $ 950 thousand was recorded during the year ended december 31 , 2017. net loan loss recoveries were $ 367 thousand during the year ended december 31 , 2018 , compared with net loan charge-offs of $ 569 thousand during the prior year . at december 31 , 2018 , relying on our alll methodology , which uses criteria such as risk factors and historical loss rates , and given the ongoing improvements in asset quality , we believe the alll is adequate . there is , however , no assurance that future loan and lease losses will not exceed the levels provided for in the alll and could possibly result in additional charges to the provision for loan and lease losses . nonperforming loans , which include nonaccrual loans and accruing loans past due over 90 days , decreased by $ 1.7 million to $ 4.1 million , or 0.44 % of gross loans , as of december 31 , 2018 , compared to $ 5.8 million , or 0.66 % of gross loans as of december 31 , 2017. the decrease in nonperforming loans was primarily due to repayments totaling $ 1.2 million from one commercial loan and one commercial real estate loan . past due loans as of december 31 , 2018 increased to $ 13.9 million , compared to $ 2.3 million as of december 31 , 2017. the increase in past due loans was primarily due to three commercial real estate loans totaling $ 12.1 million . we believe that risk grading for past due and nonperforming loans appropriately reflects the risk associated with the past due loans . see note 5 loans in the notes to consolidated financial statements in this document for further detail on the alll and the loan portfolio . premises and equipment totaled $ 13.1 million at december 31 , 2018 , a decrease of $ 1.6 million compared to $ 14.7 million at december 31 , 2017. the decrease was primarily due to provision for depreciation and amortization recognized during the current year . our oreo balance at december 31 , 2018 was $ 31 thousand compared to $ 35 thousand at december 31 , 2017. for the year ended december 31 , 2018 , we transferred five foreclosed properties in the amount of $ 140 thousand to oreo . during 2018 , we sold five properties with balances of $ 144 thousand for a net gain of $ 73 thousand . see note 8 , other real estate owned in the notes to consolidated financial statements in this document , for further details relating to our oreo portfolio . bank-owned life insurance increased $ 512 thousand during the year ended december 31 , 2018 to $ 22.4 million compared to $ 21.9 million at december 31 , 2017. our net deferred tax assets were $ 7.0 million at december 31 , 2018 compared to $ 6.5 million at december 31 , 2017. other assets which include the bank 's investment in qualified zone academy bonds , federal home loan bank of san francisco stock and low income housing tax credit partnerships totaled $ 22.5 million at december 31 , 2018 compared to $ 21.3 million at december 31 , 2017. total deposits at december 31 , 2018 , increased $ 29 million or 3 % to $ 1.132 billion compared to december 31 , 2017 . ● total non-maturing deposits increased $ 65.9 million or 7 % compared to the same date a year ago . ● certificates of deposit decreased $ 36.9 million or 19 % compared to the same date a year ago . other liabilities which include the bank 's supplemental executive retirement plan and funding obligation for investments in qualified affordable housing partnerships increased $ 563 thousand to $ 13.4 million as of december 31 , 2018 compared to $ 12.8 million at december 31 , 2017 . 29 bank of commerce holdings & subsidiaries investment securities the composition of our investment securities portfolio reflects management 's investment strategy of maintaining an appropriate level

