because we use the direct ‑expense method of accounting for our crj200 engine expense , and because we recognize revenue using the applicable fixed hourly rates under our fixed ‑rate engine contracts , the number of engine maintenance events and related expense we incur may vary between reporting period s under the fixed ‑rate engine contracts without a corresponding change to our passenger revenues that may impact t he comparability of our operating income for the presented reporting periods . because we recognize revenue in the same amount and in the same period when we incur engine maintenance expense on engines operating under our directly ‑ reimbursed engine contracts , the number of engine events and related expense we incur each reporting period does not have a direct impact on the comparability of our operating income for the presented reporting periods . we have an agreement with a third ‑party vendor to provide long ‑term engine maintenance covering scheduled and unscheduled repairs for engines on our crj700s and e175s operating under our fixed ‑ rate engine contracts ( a “ power-by- the - hour agreement ” ) . under the terms of the power-by-the-hour agreement , we are obligated to pay a set dollar amount per engine hour flown on a monthly basis and the vendor assumes the obligation to repair the engines at no additional cost to us , subject to certain specified exclusions . thus , under the power-by-the-hour agreement , we expense the engine maintenance costs as flight hours are incurred on the engines and using the contractual rate set forth in the agreement . because we record engine maintenance expense based on the fixed hourly rate pursuant to the power-by-the-hour agreement on our crj700s and e175s operating under our fixed ‑rate engine contracts , and because we recognize revenue using the applicable fixed hourly rates under our fixed ‑rate engine contracts , the number of engine events and related expense we incur each reporting period does not have a direct impact on the comparability of our operating income for the presented reporting periods . the table below summarizes how we are compensated by our major partners under our flying contracts for engine expense and the method we use to recognize the corresponding expense . flying contract compensation of engine expense expense recognition skywest delta connection directly ‑reimbursed engine contracts direct expense method expressjet delta connection directly ‑reimbursed engine contracts direct expense method skywest united express ( crj200 ) fixed ‑rate engine contracts direct expense method skywest united express ( crj700 ) fixed ‑rate engine contracts power-by-the-hour agreement skywest united express ( e175 ) fixed ‑rate engine contracts power-by-the-hour agreement expressjet united ( crj200 ) fixed ‑rate engine contracts direct expense method expressjet united ( erj145 ) directly ‑reimbursed engine contracts power-by-the-hour agreement alaska agreement ( crj700 ) fixed ‑rate engine contracts power-by-the-hour agreement alaska agreement ( e175 ) fixed ‑rate engine contracts power-by-the-hour agreement skywest american agreement ( crj200 ) fixed ‑rate engine contracts direct expense method expressjet american agreement ( crj200 ) fixed ‑rate engine contracts direct expense method historically , multiple contractual relationships with major airlines have enabled us to reduce our reliance on any single major airline code and to enhance and stabilize operating results through a mix of fixed ‑fee flying arrangements and our pro ‑rate flying arrangements . for the year ended december 31 , 201 5 , contract flying revenue and pro ‑rate revenue represented approximately 88 % and 12 % , respectively , of our total passenger revenues . on contract routes , the major airline partner controls scheduling , ticketing , pricing and seat inventories and we are compensated by the major airline partner at contracted rates based on completed block hours , flight departures and other operating measures . financial highlights we had total operating revenues of $ 3 . 1 billion for the year ended december 31 , 201 5 , a 4.4 % decrease , compared to total operating revenues of $ 3 . 2 billion for the year ended december 31 , 201 4 . we had a net income of 33 $ 117.8 million , or $ 2.27 per diluted share , for the year ended december 31 , 201 5 , compared to a net loss of $ 24.2 million , or $ ( 0.47 ) per diluted share , for the year ended december 31 , 2014 . the significant items affecting our financial performance during the year ended december 31 , 2015 are outlined below : revenue the number of aircraft we have in scheduled service and the number of block hours we generate on our flights are primary drivers to our passenger revenues under our fixed-fee flying agreements . during 2015 , we had a significant change in the number of aircraft operating under fixed- fee agreements . our primary objective in the fleet change is to improve our profitability by adding new aircraft to fixed-fee agreements at improved economics , including the e175 aircraft , while removing aircraft that were operating under less profitable arrangements . as summarized under the fleet activity section below , from december 31 , 2014 to december 31 , 2015 , we removed 103 aircraft from service that were operating under less profitable flying contracts and added 46 aircraft to new or existing fixed-fee flying arrangements at improved economics . the number of aircraft available for scheduled service decreased from 717 aircraft at december 31 , 2014 to 660 at december 31 , 2015 , or by 8.6 % . story_separator_special_tag replace_table_token_14_th salaries , wages and employee benefits . salaries , wages and employee benefits de creased $ 54 .8 million , or 4.4 % , during the year ended december 31 , 2015 , compared to the year ended december 31 , 201 4 . the decrease in salaries , wages and employee benefits was primarily due to the decrease in our fleet size and related decrease in the number of departures and block hours compared to the year ended december 31 , 201 4 , which was partially offset by additional training costs for the e175 deliveries and an increase in employee benefit costs . aircraft maintenance , materials and repairs . aircraft maintenance expense decreased $ 77 . 9 million , or 11 . 4 % , during the year ended december 31 , 2015 , compared to the year ended december 31 201 4 . the following table summarizes the effect of directly- reimbursed engine maintenance costs under our fixed-fee flying arrangements included in our aircraft maintenance expense for the periods indicated ( dollar amounts in thousands ) . replace_table_token_15_th other aircraft maintenance , materials and repairs , excluding our directly-reimbursed engine overhaul costs , decreased $ 41.5 million , or 7 . 5 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 2014 . the decrease in aircraft maintenance expense ( excluding directly-reimbursed engine overhaul costs ) was primarily due to a reduction in direct maintenance costs resulting from a reduced fleet size , partially offset by an increase in power-by-the-hour maintenance costs associated with the additional e175 aircraft added to our fleet since 2014 . the decrease in our engine overhaul costs incurred under our directly ‑reimbursed engine contracts , was primarily due to a reduced number of engine overhaul events in 2015 compared to 2014. aircraft rentals . aircraft rentals decreased $ 31 . 6 million , or 10 . 4 % , during the year ended december 31 , 2015 , compared to the year ended december 31 , 201 4 . the decrease was primarily due to a reduction in the number of leased aircraft in our fleet and lower aircraft lease renewal rates since 201 4 . 39 depreciation and amortization . depreciation and amortization expense increased $ 4 . 8 million , or 1 . 9 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . the increase in depreciation and amortization expense was primarily due to the purchase of additional e175 aircraft and spare engines in 2015 that was significantly offset by the reduction in fixed asset depreciation expense that resulted from our removal of all emb 120 aircraft from service in early 2015 . fuel . fuel costs decreased $ 75.1 million , or 38.9 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . the decrease in fuel cost was primarily due to the decrease in the average fuel cost per gallon in 201 5 compared to 201 4 , along with a decrease in the volume in gallons that we purchased under our fixed-fee contracts . the following table summarizes our aircraft fuel expenses ( less directly-reimbursed fuel expense under our fixed-fee flying arrangements ) for the periods indicated ( dollar amounts in thousands ) . replace_table_token_16_th the average fuel cost per gallon was $ 2 . 09 and $ 3.33 for the years ended december 31 , 201 5 and 2014 , respectively . the following table summarizes the gallons of fuel we purchased directly and our fuel expense , for the periods indicated : replace_table_token_17_th ground handling service . ground handling service expense decreased $ 41 .2 million , or 33.3 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . the decrease in ground handling service expense was primarily due to a reduction in the number of locations for which skywest airlines provide d ground handling services subsequent to december 31 , 2014. special items . special items for the year ended december 31 , 2014 included impairment charges to write ‑down owned emb120 aircraft , including capitalized engine overhaul costs , and related long ‑lived assets to their estimated fair value and accrued obligations on leased aircraft and related costs of $ 57.1 million . the special item associated with the emb120 aircraft was triggered by our decision in november 2014 to remove the emb120 aircraft from service by the end of the second quarter of 2015. the special item additionally consisted of impairment charges to write ‑down certain erj145 long ‑lived assets , including spare engines and capitalized aircraft improvements , to their estimated fair value and accrued obligations on leased aircraft and related costs of $ 12.9 million . the special item associated with the erj145 aircraft was triggered by our execution of an amended and restated contract with united in november 2014. the amended and restated contract provides for accelerated lease termination dates of certain erj145 aircraft and advances the termination date of the expressjet united erj agreement to operate the erj145s from the year 2020 to 2017. the special item also includes the write ‑down of assets associated with the disposition of our paint facility located in saltillo , mexico of $ 4.8 million . we sold the saltillo paint facility during the year ended december 31 , 2014. station rents and landing fees . station rents and landing fees expense in creased $ 3 . 1 million , or 6.2 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . e xcluding our directly-reimbursed expenses incurred under our fixed-fee contracts , s tation rents and landing fees increased $ 4 . 8 million ,

liquidity and capital resources sources and uses of cash—201 5 compared to 201 4 cash position and liquidity . the following table provides a summary of the net cash provided by ( used in ) our operating , investing and financing activities for the years ended december 31 , 201 5 and 201 4 , and our total cash and marketable securities position as of december 31 , 201 5 and december 31 , 201 4 ( in thousands ) . replace_table_token_30_th replace_table_token_31_th cash flows from operating activities . net cash provided from operating activities in creased $ 13 4 . 6 million , or 4 7 . 1 % , during 201 5 , compared to 201 4 . the primary factors impacting our cash provided from operating activities include : our net income improved $ 1 42.0 million from 2014 to 2015 and our deferred income taxes increased $ 73.8 million from 2014 to 2015. additionally , the combination of the 2014 special items , the 2014 gain on sale of our trip shares and the 2015 gain on early debt payoff resulted in a net decrease to cash from operations of $ 83.6 million . cash flows from investing activities . net cas h used in investing activities de creased $ 1 5 . 5 million , or 2 . 7 % during 201 5 , compared to 201 4. the de crease in cash used in investing activities was primarily due to the net sales of 51 marketable securities which increased $ 57.4 million during 2015 , compared to 2014 along with the decrease of other assets of $ 16.0 million during 2015 , compared to 2014. these changes were partially offset by the acquisition of 25 e175 aircraft along with the related rotable spare assets in 2015 , compared to 20 e175 aircraft , one used crj700 aircraft and 20 used crj200 engines along with the related rotable spare assets purchased in 2014 , which in total represented an increase of $ 5 7.4 million compared to the aircraft acquisition and related rotable spare aircraft purchases from 201 4 .


 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 sources and uses of cash—201 5 compared to 201 4 cash position and liquidity . the following table provides a summary of the net cash provided by ( used in ) our operating , investing and financing activities for the years ended december 31 , 201 5 and 201 4 , and our total cash and marketable securities position as of december 31 , 201 5 and december 31 , 201 4 ( in thousands ) . replace_table_token_30_th replace_table_token_31_th cash flows from operating activities . net cash provided from operating activities in creased $ 13 4 . 6 million , or 4 7 . 1 % , during 201 5 , compared to 201 4 . the primary factors impacting our cash provided from operating activities include : our net income improved $ 1 42.0 million from 2014 to 2015 and our deferred income taxes increased $ 73.8 million from 2014 to 2015. additionally , the combination of the 2014 special items , the 2014 gain on sale of our trip shares and the 2015 gain on early debt payoff resulted in a net decrease to cash from operations of $ 83.6 million . cash flows from investing activities . net cas h used in investing activities de creased $ 1 5 . 5 million , or 2 . 7 % during 201 5 , compared to 201 4. the de crease in cash used in investing activities was primarily due to the net sales of 51 marketable securities which increased $ 57.4 million during 2015 , compared to 2014 along with the decrease of other assets of $ 16.0 million during 2015 , compared to 2014. these changes were partially offset by the acquisition of 25 e175 aircraft along with the related rotable spare assets in 2015 , compared to 20 e175 aircraft , one used crj700 aircraft and 20 used crj200 engines along with the related rotable spare assets purchased in 2014 , which in total represented an increase of $ 5 7.4 million compared to the aircraft acquisition and related rotable spare aircraft purchases from 201 4 .
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 Suspicious Activity Report : because we use the direct ‑expense method of accounting for our crj200 engine expense , and because we recognize revenue using the applicable fixed hourly rates under our fixed ‑rate engine contracts , the number of engine maintenance events and related expense we incur may vary between reporting period s under the fixed ‑rate engine contracts without a corresponding change to our passenger revenues that may impact t he comparability of our operating income for the presented reporting periods . because we recognize revenue in the same amount and in the same period when we incur engine maintenance expense on engines operating under our directly ‑ reimbursed engine contracts , the number of engine events and related expense we incur each reporting period does not have a direct impact on the comparability of our operating income for the presented reporting periods . we have an agreement with a third ‑party vendor to provide long ‑term engine maintenance covering scheduled and unscheduled repairs for engines on our crj700s and e175s operating under our fixed ‑ rate engine contracts ( a “ power-by- the - hour agreement ” ) . under the terms of the power-by-the-hour agreement , we are obligated to pay a set dollar amount per engine hour flown on a monthly basis and the vendor assumes the obligation to repair the engines at no additional cost to us , subject to certain specified exclusions . thus , under the power-by-the-hour agreement , we expense the engine maintenance costs as flight hours are incurred on the engines and using the contractual rate set forth in the agreement . because we record engine maintenance expense based on the fixed hourly rate pursuant to the power-by-the-hour agreement on our crj700s and e175s operating under our fixed ‑rate engine contracts , and because we recognize revenue using the applicable fixed hourly rates under our fixed ‑rate engine contracts , the number of engine events and related expense we incur each reporting period does not have a direct impact on the comparability of our operating income for the presented reporting periods . the table below summarizes how we are compensated by our major partners under our flying contracts for engine expense and the method we use to recognize the corresponding expense . flying contract compensation of engine expense expense recognition skywest delta connection directly ‑reimbursed engine contracts direct expense method expressjet delta connection directly ‑reimbursed engine contracts direct expense method skywest united express ( crj200 ) fixed ‑rate engine contracts direct expense method skywest united express ( crj700 ) fixed ‑rate engine contracts power-by-the-hour agreement skywest united express ( e175 ) fixed ‑rate engine contracts power-by-the-hour agreement expressjet united ( crj200 ) fixed ‑rate engine contracts direct expense method expressjet united ( erj145 ) directly ‑reimbursed engine contracts power-by-the-hour agreement alaska agreement ( crj700 ) fixed ‑rate engine contracts power-by-the-hour agreement alaska agreement ( e175 ) fixed ‑rate engine contracts power-by-the-hour agreement skywest american agreement ( crj200 ) fixed ‑rate engine contracts direct expense method expressjet american agreement ( crj200 ) fixed ‑rate engine contracts direct expense method historically , multiple contractual relationships with major airlines have enabled us to reduce our reliance on any single major airline code and to enhance and stabilize operating results through a mix of fixed ‑fee flying arrangements and our pro ‑rate flying arrangements . for the year ended december 31 , 201 5 , contract flying revenue and pro ‑rate revenue represented approximately 88 % and 12 % , respectively , of our total passenger revenues . on contract routes , the major airline partner controls scheduling , ticketing , pricing and seat inventories and we are compensated by the major airline partner at contracted rates based on completed block hours , flight departures and other operating measures . financial highlights we had total operating revenues of $ 3 . 1 billion for the year ended december 31 , 201 5 , a 4.4 % decrease , compared to total operating revenues of $ 3 . 2 billion for the year ended december 31 , 201 4 . we had a net income of 33 $ 117.8 million , or $ 2.27 per diluted share , for the year ended december 31 , 201 5 , compared to a net loss of $ 24.2 million , or $ ( 0.47 ) per diluted share , for the year ended december 31 , 2014 . the significant items affecting our financial performance during the year ended december 31 , 2015 are outlined below : revenue the number of aircraft we have in scheduled service and the number of block hours we generate on our flights are primary drivers to our passenger revenues under our fixed-fee flying agreements . during 2015 , we had a significant change in the number of aircraft operating under fixed- fee agreements . our primary objective in the fleet change is to improve our profitability by adding new aircraft to fixed-fee agreements at improved economics , including the e175 aircraft , while removing aircraft that were operating under less profitable arrangements . as summarized under the fleet activity section below , from december 31 , 2014 to december 31 , 2015 , we removed 103 aircraft from service that were operating under less profitable flying contracts and added 46 aircraft to new or existing fixed-fee flying arrangements at improved economics . the number of aircraft available for scheduled service decreased from 717 aircraft at december 31 , 2014 to 660 at december 31 , 2015 , or by 8.6 % . story_separator_special_tag replace_table_token_14_th salaries , wages and employee benefits . salaries , wages and employee benefits de creased $ 54 .8 million , or 4.4 % , during the year ended december 31 , 2015 , compared to the year ended december 31 , 201 4 . the decrease in salaries , wages and employee benefits was primarily due to the decrease in our fleet size and related decrease in the number of departures and block hours compared to the year ended december 31 , 201 4 , which was partially offset by additional training costs for the e175 deliveries and an increase in employee benefit costs . aircraft maintenance , materials and repairs . aircraft maintenance expense decreased $ 77 . 9 million , or 11 . 4 % , during the year ended december 31 , 2015 , compared to the year ended december 31 201 4 . the following table summarizes the effect of directly- reimbursed engine maintenance costs under our fixed-fee flying arrangements included in our aircraft maintenance expense for the periods indicated ( dollar amounts in thousands ) . replace_table_token_15_th other aircraft maintenance , materials and repairs , excluding our directly-reimbursed engine overhaul costs , decreased $ 41.5 million , or 7 . 5 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 2014 . the decrease in aircraft maintenance expense ( excluding directly-reimbursed engine overhaul costs ) was primarily due to a reduction in direct maintenance costs resulting from a reduced fleet size , partially offset by an increase in power-by-the-hour maintenance costs associated with the additional e175 aircraft added to our fleet since 2014 . the decrease in our engine overhaul costs incurred under our directly ‑reimbursed engine contracts , was primarily due to a reduced number of engine overhaul events in 2015 compared to 2014. aircraft rentals . aircraft rentals decreased $ 31 . 6 million , or 10 . 4 % , during the year ended december 31 , 2015 , compared to the year ended december 31 , 201 4 . the decrease was primarily due to a reduction in the number of leased aircraft in our fleet and lower aircraft lease renewal rates since 201 4 . 39 depreciation and amortization . depreciation and amortization expense increased $ 4 . 8 million , or 1 . 9 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . the increase in depreciation and amortization expense was primarily due to the purchase of additional e175 aircraft and spare engines in 2015 that was significantly offset by the reduction in fixed asset depreciation expense that resulted from our removal of all emb 120 aircraft from service in early 2015 . fuel . fuel costs decreased $ 75.1 million , or 38.9 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . the decrease in fuel cost was primarily due to the decrease in the average fuel cost per gallon in 201 5 compared to 201 4 , along with a decrease in the volume in gallons that we purchased under our fixed-fee contracts . the following table summarizes our aircraft fuel expenses ( less directly-reimbursed fuel expense under our fixed-fee flying arrangements ) for the periods indicated ( dollar amounts in thousands ) . replace_table_token_16_th the average fuel cost per gallon was $ 2 . 09 and $ 3.33 for the years ended december 31 , 201 5 and 2014 , respectively . the following table summarizes the gallons of fuel we purchased directly and our fuel expense , for the periods indicated : replace_table_token_17_th ground handling service . ground handling service expense decreased $ 41 .2 million , or 33.3 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . the decrease in ground handling service expense was primarily due to a reduction in the number of locations for which skywest airlines provide d ground handling services subsequent to december 31 , 2014. special items . special items for the year ended december 31 , 2014 included impairment charges to write ‑down owned emb120 aircraft , including capitalized engine overhaul costs , and related long ‑lived assets to their estimated fair value and accrued obligations on leased aircraft and related costs of $ 57.1 million . the special item associated with the emb120 aircraft was triggered by our decision in november 2014 to remove the emb120 aircraft from service by the end of the second quarter of 2015. the special item additionally consisted of impairment charges to write ‑down certain erj145 long ‑lived assets , including spare engines and capitalized aircraft improvements , to their estimated fair value and accrued obligations on leased aircraft and related costs of $ 12.9 million . the special item associated with the erj145 aircraft was triggered by our execution of an amended and restated contract with united in november 2014. the amended and restated contract provides for accelerated lease termination dates of certain erj145 aircraft and advances the termination date of the expressjet united erj agreement to operate the erj145s from the year 2020 to 2017. the special item also includes the write ‑down of assets associated with the disposition of our paint facility located in saltillo , mexico of $ 4.8 million . we sold the saltillo paint facility during the year ended december 31 , 2014. station rents and landing fees . station rents and landing fees expense in creased $ 3 . 1 million , or 6.2 % , during the year ended december 31 , 201 5 , compared to the year ended december 31 , 201 4 . e xcluding our directly-reimbursed expenses incurred under our fixed-fee contracts , s tation rents and landing fees increased $ 4 . 8 million ,

