our c & i segment provides a wide range of services including design , installation , maintenance and repair of commercial and industrial wiring , installation of traffic networks and the installation of bridge , roadway and tunnel lighting . in our c & i segment , we generally provide our electric construction and maintenance services as a subcontractor to general contractors in the c & i industry as well as directly to facility owners . our c & i operations are primarily in the western and northeastern united states and in western canada where we have sufficient scale to deploy the level of resources necessary to achieve significant market share . we concentrate our efforts on projects where our technical and project management expertise are critical to successful and timely execution . the majority of c & i contracts cover electrical contracting services for airports , hospitals , data centers , hotels , stadiums , convention centers , manufacturing plants , processing facilities , waste-water treatment facilities , mining facilities and transportation control and management systems . for the year ended december 31 , 2017 , our c & i revenues were $ 523.9 million , or 37.3 % , of our revenue , compared to $ 323.5 million , or 28.3 % , of our revenue for the year ended december 31 , 2016 and $ 266.8 million , or 25.1 % , of our revenue for the year ended december 31 , 2015. measured by revenues in our c & i segment , we provided 63.7 % , 73.4 % and 71.6 % of our services under fixed-price contracts for the years ended december 31 , 2017 , 2016 and 2015 , respectively . overview-revenue and gross margins revenue recognition . we recognize revenue on a percentage-of-completion method of accounting , which is commonly used in the construction industry . the percentage-of-completion accounting method results in recognizing contract revenues and earnings ratably over the contract term in proportion to our incurrence of contract costs . the profits or losses recognized on individual contracts are based on estimates of contract revenues , costs and profitability . contract losses are recognized in full when determined , and contract profit estimates are adjusted based on ongoing reviews of contract profitability . changes in job performance , labor costs , equipment costs , job conditions , weather , estimated profitability and final contract settlements may result in revisions to costs and income and their effects are recognized in the period in which the revisions are determined . we record adjustments to estimated costs of contracts when we believe the change in estimate is probable and the amounts can be reasonably estimated . these adjustments could result in either increases or decreases in profit margins . gross margins . our gross margin can vary between periods as a result of many factors , some of which are beyond our control . these factors include : the mix of revenue derived from the industries we serve , the size and duration of our projects , the mix of business conducted in different parts of the united states and canada , the mix in service and maintenance work compared to new construction work , the amount of work that we subcontract , the amount of material we supply , changes in labor , equipment or insurance costs , seasonal weather patterns , changes in fleet utilization , pricing pressures due to competition , efficiency of work performance , fluctuations in commodity prices of materials , delays in the timing of projects and other factors . the gross margins we record in the current period may not be indicative of margins in future periods . overview-economic , industry and market factors we operate in competitive markets , which can result in pricing pressures for the services we provide . work is often awarded through a bidding and selection process , where price is always a principal factor . we generally focus on managing our profitability by : selecting projects that we believe will provide attractive margins ; actively monitoring the costs of completing our projects ; holding customers accountable for costs related to changes to contract specifications ; and rewarding our employees for controlling costs . the demand for construction and maintenance services from our customers has been , and will likely continue to be , cyclical in nature and vulnerable to downturns in the markets we serve as well as the economy in general . the financial condition of our customers and their access to capital , variations in the margins of projects performed during any particular period , and regional and national economic conditions in the united states and canada may materially affect results . project schedules , particularly in connection with larger , multi-year projects , can also create fluctuations in our revenues . other market and industry factors , such as changes to our customers ' capital spending plans or delays in regulatory approvals can affect project schedules . changes in technology , tax and other incentives and new or changing regulatory requirements 32 affecting the industries we serve can impact demand for our services . while we actively monitor economic , industry and market factors affecting our business , we can not predict the impact such factors may have on our future results of operations , liquidity and cash flows . as a result of economic , industry and market factors , our operating results in any particular period or year may not be indicative of the results that can be expected for any other period or for any other year . overview-seasonality and nature of our work environment although our revenues are primarily driven by spending patterns in our customers ' industries , our revenues , particularly those derived from our t & d segment , and results of operations can be subject to seasonal variations . story_separator_special_tag a significant shift in project mix or timing could impact fleet utilization , causing gross margins to vary . our team of trained estimators helps us to determine potential costs and revenues and make informed decisions on whether to bid for a project and , if bid , the rates to use in estimating the costs for that bid . the ability to accurately estimate labor , equipment , subcontracting and material costs in connection with a new project may affect the gross margins achieved for the project . selling , general and administrative expenses selling , general and administrative expenses consist primarily of compensation , related benefits and employee costs for management and administrative personnel , office rent and utilities , stock compensation , communications , professional fees , depreciation , it expenses , marketing costs and bad debt expense . 36 consolidated results of operations the following table sets forth selected statements of operations data and such data as a percentage of revenues for the years indicated : replace_table_token_9_th year ended december 31 , 2017 compared to the year ended december 31 , 2016 revenues . revenues increased $ 260.8 million , or 22.8 % , to $ 1.403 billion for the year ended december 31 , 2017 from $ 1.142 billion for the year ended december 31 , 2016. the increase was primarily due to increased spending from existing c & i customers , the wpe acquisition in late 2016 , higher revenue from large transmission projects and an increase in distribution projects . gross margin . gross margin decreased to 8.9 % for the year ended december 31 , 2017 from 11.8 % for the year ended december 31 , 2016. the decrease in gross margin was primarily due to write-downs on three projects . two projects in the midwest u.s. were significantly impacted by weather resulting in unanticipated costs associated with right-of-way access , lower productivity and increased road damage and repair requirements . as a result , we wrote down $ 4.8 million for these projects in 2017. one t & d project in canada experienced cost impacts mainly associated with project delays and schedule extensions . although we are working with our clients to recover these costs , we have not recognized all of the revenues relating to various pending project claims and change orders , which resulted in write-downs on this project of $ 4.4 million . margins were also negatively impacted from significant revenue on a large transmission project that had lower than average margins due to a high mix of material and subcontractor costs and lower than average margin on a certain distribution project , as well as costs associated with organic and acquisition growth . in addition , during 2017 we had a higher mix of revenue in our c & i segment and distribution work , compared to transmission work which generally carries a higher margin . these impacts were partially offset by project efficiencies and settlements related to previously unrecognized revenues on a project claim and pending change orders . changes in estimates of gross profit on certain projects , including those discussed above , resulted in gross margin decreases of 0.7 % for the year ended december 31 , 2017. changes in estimates of gross profit on certain projects resulted in gross margin decreases of 0.2 % for the year ended december 31 , 2016. gross profit . gross profit decreased $ 9.7 million , or 7.2 % , to $ 125.0 million for year ended december 31 , 2017 from $ 134.7 million for the year ended december 31 , 2016 , primarily due to lower overall gross margin , partially offset by higher revenue . 37 selling , general and administrative expenses . selling , general and administrative expenses ( sg & a ) , which were $ 98.6 million for the year ended december 31 , 2017 , increased $ 2.2 million from $ 96.4 million for the year ended december 31 , 2016. the year-over-year increase was primarily due to $ 6.8 million of incremental costs associated with our expansion into new geographic markets and strategic acquisitions as well as higher payroll costs to support operations , largely offset by lower bonus and profit sharing costs . additionally , $ 1.0 million of costs associated with activist investor activities were incurred in 2016. as a percentage of revenues , sg & a decreased to 7.0 % for the year ended december 31 , 2017 from 8.4 % for the year ended december 31 , 2016. gain on sale of property and equipment . gains from the sale of property and equipment in the year ended december 31 , 2017 were $ 3.7 million compared to $ 1.3 million in the year ended december 31 , 2016. gains from the sale of property and equipment are attributable to routine sales of property and equipment no longer useful or valuable to our ongoing operations . interest expense . interest expense was $ 2.6 million for the year ended december 31 , 2017 compared to $ 1.3 million for the year ended december 31 , 2016. this increase was primarily attributable to the amount and duration of borrowings outstanding under our line of credit during the year ended december 31 , 2017 as compared to the year ended december 31 , 2016. other income ( expense ) . other expense was $ 2.3 million for the year ended december 31 , 2017 compared to other income of $ 0.9 million for the year ended december 31 , 2016. the change was largely due to a $ 2.3 million reversal of previously recognized contingent consideration related to the finalization of margin guarantees on certain contracts associated with the acquisition of wpe . income tax expense . the provision for income taxes was $ 3.5 million for the year ended december 31 , 2017 , with an effective tax rate of 14.1 % , compared to a

liquidity and capital resources as of december 31 , 2017 and 2016 , we had working capital of $ 191.2 million and $ 146.7 million , respectively . we define working capital as current assets less current liabilities . during the year ended december 31 , 2017 , operating activities of our business used cash of $ 9.2 million , compared to providing cash of $ 54.5 million for the year ended december 31 , 2016. cash flow from operations is primarily influenced by demand for our services , operating margins , timing of contract performance and the type of services we provide to our customers . net cash used in or provided by operating activities is driven by our net income adjusted for changes in operating assets and liabilities and non-cash items including , but not limited to , depreciation and amortization , stock-based compensation , deferred income taxes , and the gain on sale of property and equipment . the $ 63.7 million year-over-year decline in net cash from operating activities was primarily due to unfavorable changes in various working capital accounts ( accounts receivable , costs and estimated earnings in excess of billings on uncompleted contracts , accounts payable and billings in excess of costs and estimated earnings on uncompleted contracts ) of $ 31.3 million . additionally , a $ 19.0 million decline 41 in other liabilities , primarily attributable to lower bonus and profit sharing accruals and a $ 9.3 million unfavorable non-cash change in deferred taxes , due primarily to the tax act . the changes in various working capital accounts are generally due to normal timing fluctuations in our operating activities .


 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.
     ```liquidity and capital resources as of december 31 , 2017 and 2016 , we had working capital of $ 191.2 million and $ 146.7 million , respectively . we define working capital as current assets less current liabilities . during the year ended december 31 , 2017 , operating activities of our business used cash of $ 9.2 million , compared to providing cash of $ 54.5 million for the year ended december 31 , 2016. cash flow from operations is primarily influenced by demand for our services , operating margins , timing of contract performance and the type of services we provide to our customers . net cash used in or provided by operating activities is driven by our net income adjusted for changes in operating assets and liabilities and non-cash items including , but not limited to , depreciation and amortization , stock-based compensation , deferred income taxes , and the gain on sale of property and equipment . the $ 63.7 million year-over-year decline in net cash from operating activities was primarily due to unfavorable changes in various working capital accounts ( accounts receivable , costs and estimated earnings in excess of billings on uncompleted contracts , accounts payable and billings in excess of costs and estimated earnings on uncompleted contracts ) of $ 31.3 million . additionally , a $ 19.0 million decline 41 in other liabilities , primarily attributable to lower bonus and profit sharing accruals and a $ 9.3 million unfavorable non-cash change in deferred taxes , due primarily to the tax act . the changes in various working capital accounts are generally due to normal timing fluctuations in our operating activities .
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 Suspicious Activity Report : our c & i segment provides a wide range of services including design , installation , maintenance and repair of commercial and industrial wiring , installation of traffic networks and the installation of bridge , roadway and tunnel lighting . in our c & i segment , we generally provide our electric construction and maintenance services as a subcontractor to general contractors in the c & i industry as well as directly to facility owners . our c & i operations are primarily in the western and northeastern united states and in western canada where we have sufficient scale to deploy the level of resources necessary to achieve significant market share . we concentrate our efforts on projects where our technical and project management expertise are critical to successful and timely execution . the majority of c & i contracts cover electrical contracting services for airports , hospitals , data centers , hotels , stadiums , convention centers , manufacturing plants , processing facilities , waste-water treatment facilities , mining facilities and transportation control and management systems . for the year ended december 31 , 2017 , our c & i revenues were $ 523.9 million , or 37.3 % , of our revenue , compared to $ 323.5 million , or 28.3 % , of our revenue for the year ended december 31 , 2016 and $ 266.8 million , or 25.1 % , of our revenue for the year ended december 31 , 2015. measured by revenues in our c & i segment , we provided 63.7 % , 73.4 % and 71.6 % of our services under fixed-price contracts for the years ended december 31 , 2017 , 2016 and 2015 , respectively . overview-revenue and gross margins revenue recognition . we recognize revenue on a percentage-of-completion method of accounting , which is commonly used in the construction industry . the percentage-of-completion accounting method results in recognizing contract revenues and earnings ratably over the contract term in proportion to our incurrence of contract costs . the profits or losses recognized on individual contracts are based on estimates of contract revenues , costs and profitability . contract losses are recognized in full when determined , and contract profit estimates are adjusted based on ongoing reviews of contract profitability . changes in job performance , labor costs , equipment costs , job conditions , weather , estimated profitability and final contract settlements may result in revisions to costs and income and their effects are recognized in the period in which the revisions are determined . we record adjustments to estimated costs of contracts when we believe the change in estimate is probable and the amounts can be reasonably estimated . these adjustments could result in either increases or decreases in profit margins . gross margins . our gross margin can vary between periods as a result of many factors , some of which are beyond our control . these factors include : the mix of revenue derived from the industries we serve , the size and duration of our projects , the mix of business conducted in different parts of the united states and canada , the mix in service and maintenance work compared to new construction work , the amount of work that we subcontract , the amount of material we supply , changes in labor , equipment or insurance costs , seasonal weather patterns , changes in fleet utilization , pricing pressures due to competition , efficiency of work performance , fluctuations in commodity prices of materials , delays in the timing of projects and other factors . the gross margins we record in the current period may not be indicative of margins in future periods . overview-economic , industry and market factors we operate in competitive markets , which can result in pricing pressures for the services we provide . work is often awarded through a bidding and selection process , where price is always a principal factor . we generally focus on managing our profitability by : selecting projects that we believe will provide attractive margins ; actively monitoring the costs of completing our projects ; holding customers accountable for costs related to changes to contract specifications ; and rewarding our employees for controlling costs . the demand for construction and maintenance services from our customers has been , and will likely continue to be , cyclical in nature and vulnerable to downturns in the markets we serve as well as the economy in general . the financial condition of our customers and their access to capital , variations in the margins of projects performed during any particular period , and regional and national economic conditions in the united states and canada may materially affect results . project schedules , particularly in connection with larger , multi-year projects , can also create fluctuations in our revenues . other market and industry factors , such as changes to our customers ' capital spending plans or delays in regulatory approvals can affect project schedules . changes in technology , tax and other incentives and new or changing regulatory requirements 32 affecting the industries we serve can impact demand for our services . while we actively monitor economic , industry and market factors affecting our business , we can not predict the impact such factors may have on our future results of operations , liquidity and cash flows . as a result of economic , industry and market factors , our operating results in any particular period or year may not be indicative of the results that can be expected for any other period or for any other year . overview-seasonality and nature of our work environment although our revenues are primarily driven by spending patterns in our customers ' industries , our revenues , particularly those derived from our t & d segment , and results of operations can be subject to seasonal variations . story_separator_special_tag a significant shift in project mix or timing could impact fleet utilization , causing gross margins to vary . our team of trained estimators helps us to determine potential costs and revenues and make informed decisions on whether to bid for a project and , if bid , the rates to use in estimating the costs for that bid . the ability to accurately estimate labor , equipment , subcontracting and material costs in connection with a new project may affect the gross margins achieved for the project . selling , general and administrative expenses selling , general and administrative expenses consist primarily of compensation , related benefits and employee costs for management and administrative personnel , office rent and utilities , stock compensation , communications , professional fees , depreciation , it expenses , marketing costs and bad debt expense . 36 consolidated results of operations the following table sets forth selected statements of operations data and such data as a percentage of revenues for the years indicated : replace_table_token_9_th year ended december 31 , 2017 compared to the year ended december 31 , 2016 revenues . revenues increased $ 260.8 million , or 22.8 % , to $ 1.403 billion for the year ended december 31 , 2017 from $ 1.142 billion for the year ended december 31 , 2016. the increase was primarily due to increased spending from existing c & i customers , the wpe acquisition in late 2016 , higher revenue from large transmission projects and an increase in distribution projects . gross margin . gross margin decreased to 8.9 % for the year ended december 31 , 2017 from 11.8 % for the year ended december 31 , 2016. the decrease in gross margin was primarily due to write-downs on three projects . two projects in the midwest u.s. were significantly impacted by weather resulting in unanticipated costs associated with right-of-way access , lower productivity and increased road damage and repair requirements . as a result , we wrote down $ 4.8 million for these projects in 2017. one t & d project in canada experienced cost impacts mainly associated with project delays and schedule extensions . although we are working with our clients to recover these costs , we have not recognized all of the revenues relating to various pending project claims and change orders , which resulted in write-downs on this project of $ 4.4 million . margins were also negatively impacted from significant revenue on a large transmission project that had lower than average margins due to a high mix of material and subcontractor costs and lower than average margin on a certain distribution project , as well as costs associated with organic and acquisition growth . in addition , during 2017 we had a higher mix of revenue in our c & i segment and distribution work , compared to transmission work which generally carries a higher margin . these impacts were partially offset by project efficiencies and settlements related to previously unrecognized revenues on a project claim and pending change orders . changes in estimates of gross profit on certain projects , including those discussed above , resulted in gross margin decreases of 0.7 % for the year ended december 31 , 2017. changes in estimates of gross profit on certain projects resulted in gross margin decreases of 0.2 % for the year ended december 31 , 2016. gross profit . gross profit decreased $ 9.7 million , or 7.2 % , to $ 125.0 million for year ended december 31 , 2017 from $ 134.7 million for the year ended december 31 , 2016 , primarily due to lower overall gross margin , partially offset by higher revenue . 37 selling , general and administrative expenses . selling , general and administrative expenses ( sg & a ) , which were $ 98.6 million for the year ended december 31 , 2017 , increased $ 2.2 million from $ 96.4 million for the year ended december 31 , 2016. the year-over-year increase was primarily due to $ 6.8 million of incremental costs associated with our expansion into new geographic markets and strategic acquisitions as well as higher payroll costs to support operations , largely offset by lower bonus and profit sharing costs . additionally , $ 1.0 million of costs associated with activist investor activities were incurred in 2016. as a percentage of revenues , sg & a decreased to 7.0 % for the year ended december 31 , 2017 from 8.4 % for the year ended december 31 , 2016. gain on sale of property and equipment . gains from the sale of property and equipment in the year ended december 31 , 2017 were $ 3.7 million compared to $ 1.3 million in the year ended december 31 , 2016. gains from the sale of property and equipment are attributable to routine sales of property and equipment no longer useful or valuable to our ongoing operations . interest expense . interest expense was $ 2.6 million for the year ended december 31 , 2017 compared to $ 1.3 million for the year ended december 31 , 2016. this increase was primarily attributable to the amount and duration of borrowings outstanding under our line of credit during the year ended december 31 , 2017 as compared to the year ended december 31 , 2016. other income ( expense ) . other expense was $ 2.3 million for the year ended december 31 , 2017 compared to other income of $ 0.9 million for the year ended december 31 , 2016. the change was largely due to a $ 2.3 million reversal of previously recognized contingent consideration related to the finalization of margin guarantees on certain contracts associated with the acquisition of wpe . income tax expense . the provision for income taxes was $ 3.5 million for the year ended december 31 , 2017 , with an effective tax rate of 14.1 % , compared to a

