we supply and transmit our members ' electric power requirements through a portfolio of resources , including generating and transmission facilities , long‑term purchase contracts and short‑term energy purchases . we own , lease , have undivided percentage interests in , or have tolling arrangements with respect to , various generating stations . additionally , we transmit power to our members through resources that we own , lease or have undivided percentage interests in , or by wheeling power across lines owned by other transmission providers . see “ business - overview- power supply and transmission ” for a description of miles of transmission lines and substations . depending on our system requirements and contractual obligations , we are likely to both purchase and sell electric power during the same fiscal period . we purchase hydroelectric power under long‑term purchase contracts . 38 these contracts constituted our original power resource , and they remain a cost‑effective power source . we also purchase , under long‑term purchase contracts with basin , all the power which we require to serve our members ' load in the eastern interconnection and fixed scheduled quantities of power in the western interconnection . our generating facilities are located in the western interconnection and generally isolated from our members ' load in the eastern interconnection . these long‑term purchase commitments represent a majority of our electric power purchases . we purchase additional power on a long and short‑term basis , including 477 mws under long-term purchase contracts from other renewable energy resources , including wind , solar and small hydro . at the same time , we have agreed to supply electric power to non‑members . in addition , we utilize market purchases to optimize our position by routinely purchasing power when the market price is lower than our incremental production cost and routinely selling power to the short‑term market after consideration of our incremental production cost when we have excess power available above our firm commitments to both members and non‑members . we also use short-term energy purchases during periods of generation outages at our facilities . 2017 developments we , along with nine other participants , are part of an informal group known as the mwtg , which was formed to develop strategies to adapt to the changing electric industry in the rocky mountain region of the western interconnection . in january 2017 , the mwtg began discussions with the spp to explore potential membership . in september 2017 , the mwtg announced plans to commence negotiations with spp regarding membership . this announcement initiated a formal spp public stakeholder process . our negotiations with spp involve our transmission facilities , generating facilities and loads that are located in the states of colorado and wyoming , along with a small portion in western nebraska and new mexico . our membership in a regional transmission organization in the western interconnection could have many benefits for our system . each of the participating entities will have a multi-step approval process involving some combination of executive , board of director , customer , city , state , and federal approvals . approval from the ferc is also required . critical accounting policies the preparation of our financial statements in conformity with gaap requires that our management make estimates and assumptions that affect the amounts reported in our consolidated financial statements . we base these estimates and assumptions on information available as of the date of the financial statements and they are not necessarily indicative of the results to be expected for the year . we consider the following accounting policies to be critical accounting policies due to the estimation involved or due to the particular significance they have on our consolidated financial statements . accounting for rate regulation . we are a rate-regulated entity and , as a result , are subject to the accounting requirements of accounting for regulated operations . in accordance with these accounting requirements , some revenues and expenses have been deferred at the discretion of our board , which has budgetary and rate‑setting authority , if it is probable that these amounts will be refunded or recovered through future rates . regulatory assets are costs we expect to recover from members based on rates approved by our board in accordance with our rate policy . regulatory liabilities represent probable future reductions in rates associated with amounts that are expected to be refunded to members based on rates approved by our board in accordance with our rate policy . we recognize regulatory assets and liabilities as expenses or as a reduction in expenses concurrent with their recovery in rates . leases . the accounting for lease transactions in conformity with gaap requires management to make various assumptions , including the discount rate , the fair market value of the leased assets and the estimated useful life , in order to determine whether a lease should be classified as operating or capital . we are the lessor under a power sales arrangement that is required to be accounted for as an operating lease since the arrangement is in substance a lease because it conveys the right to use our power generating equipment for a stated period of time . the lease revenue from this arrangement is included in other operating revenue on our consolidated statements of operations . we are the lessee under a power purchase arrangement that is required to be accounted for as an operating lease since the arrangement is in substance a lease because it conveys to us the right to use power generating equipment for a stated period of time . it is included in lease expense on our consolidated statements of operations . 39 asset retirement obligations . we account for current obligations associated with the future retirement of tangible long‑lived assets in accordance with the accounting guidance relating to asset retirement and environmental obligations . story_separator_special_tag arrangement . operating expenses purchased power decreased 79,036 mwhs to 7,249,540 mwhs in 2017 compared to 7,328,576 mwhs in 2016. the decrease in mwhs sold was due to a decrease in short-term market purchases of 328,591 mwhs , partially offset by an increase in long-term renewable energy power purchases of 194,336 mwhs and long-term firm purchases of 55,219 mwhs . although mwhs sold decreased , purchased power expense increased $ 11.4 million to $ 339.8 million in 2017 compared to $ 328.4 million in 2016. the increase in purchased power expense was primarily due to an increase of $ 11.2 million , or 24.8 percent , to $ 56.3 million in 2017 compared to $ 45.1 million in 2016 for relatively similar mwh purchases from a new wind generating facility . our purchases of power from the new wind generating facilities had a higher average cost per mwh for the first six months of 2017 compared to the same period in 2016 when we were paying a lower pre-commercial rate . additionally , purchased power expense from basin increased in 2017 compared to 2016 for relatively similar mwh purchases from basin . our purchases of power from basin had a higher average cost per mwh in 2017 compared 2016 due to basin 's rate increase in the third quarter 2016. the increase in purchase power expense was partially offset by a decrease in short-term market purchases . depreciation , amortization and depletion expense increased $ 0.5 million to $ 174.5 million in 2017 compared to $ 174.0 million in 2016. depreciation expense for generation plant increased $ 9.9 million primarily due to the shortened life associated with the anticipated december 31 , 2022 retirement date of the nucla generating station of $ 8.8 million and due to the shortened life associated with the anticipated december 31 , 2025 retirement date of the craig station 43 unit 1 of $ 2.9 million . depreciation expense for transmission assets decreased $ 6.1 million primarily due to a $ 8.9 million decrease as a result of the transmission rate study , offset by additions of equipment throughout our transmission system . depreciation expense for general plant and other decreased $ 3.3 million primarily due to a $ 5.3 million decrease as a result of the general plant rate study , offset by additions of equipment to our general plant . other income other income decreased $ 2.0 million , or 7.1 percent , to $ 26.6 million in 2017 compared to $ 28.6 million in 2016. the decrease in other income was primarily due to the patronage allocation from basin of $ 7.1 million in 2017 compared to $ 14.4 million for the same period in 2016. the decrease was partially offset by the recognition of $ 5.0 million of deferred membership withdrawal income in 2017. year ended december 31 , 2016 compared to year ended december 31 , 2015 operating revenues member electric sales decreased 34,288 mwhs to 15,746,382 mwhs in 2016 compared to 15,780,670 mwhs in 2015. the withdrawal of kcec in june 2016 resulted in a 138,650 mwhs decrease in 2016 compared to 2015. although mwhs sold decreased in 2016 , member electric sales revenue increased $ 9.0 million to $ 1.135 billion in 2016 compared to $ 1.126 billion in 2015 as a result of the new rate design implemented for 2016. see “ - factors affecting results – rates and regulation ” for a description of our rates to our members . non‑member electric sales increased 131,534 mwhs , or 6.5 percent , to 2,158,059 mwhs in 2016 compared to 2,026,525 mwhs in 2015. the increase in mwhs sold was primarily due to 599,045 mwhs in the short-term market , offset by a decrease in firm sales of 467,511 mwhs due to the expiration of several long-term power sales arrangements in march 2016 and december 2015. although non-member electric sales increased , non-member electric sales revenue decreased $ 0.9 million to $ 119.3 million in 2016 compared to $ 120.2 million in 2015. the decrease in non-member electric sales revenue was due to a decrease in firm sales of $ 17.1 million primarily due to the expiration of several long-term power sales arrangements in march 2016 and december 2015. the decrease in non-member electric sales was partially offset by the income recognition of $ 9.2 million of previously deferred non-member electric sales revenue . this recognition in 2016 was required by our board in accordance with its budgetary and rate-setting authority . in addition , non-member electric short‑term market sales increased $ 7.0 million due to the increase in mwhs sold . other operating revenue consists primarily of wheeling , transmission and lease revenues , coal sales , and revenue from supplying steam and water to a paper manufacturer located adjacent to the escalante station . wheeling revenue is received when we charge other energy companies for transmitting electricity over our transmission lines . transmission revenue is from our membership in the spp , a regional transmission organization . the lease revenue is primarily from certain power sales arrangements that are required to be accounted for as operating leases since the arrangements are in substance leases because they convey to others the right to use power generating equipment for a stated period of time . coal sales revenue results from the sale of a portion of the coal from the colowyo mine per a contract ending in 2017 to other joint owners in the yampa project . other revenue decreased $ 2.5 million to $ 87.0 million in 2016 compared to $ 89.5 million in 2015. the decrease in other operating revenue was primarily due to a decrease in lease revenue of $ 12.6 million due to the expiration of power sales arrangements at our knutson and limon generating stations . this decrease was partially offset by a $ 7.9 million increase in transmission revenue resulting from our membership in the spp and a $ 1.1 million increase

liquidity we finance our operations , working capital needs and capital expenditures from operating revenues and issuance of debt . as of december 31 , 2017 , we had $ 143.7 million in cash and cash equivalents . our committed credit arrangement as of december 31 , 2017 is as follows ( dollars in thousands ) : available authorized december 31 , amount 2017 revolving credit agreement $ 750,000 ( 1 ) $ 605,000 ( 2 ) ( 1 ) the amount of this facility that can be used to support commercial paper is limited to $ 500 million . ( 2 ) the portion of this facility that was unavailable at december 31 , 2017 was $ 145 million which was dedicated to support outstanding commercial paper . the revolving credit agreement has aggregate commitments of $ 750 million which includes a swingline sublimit of $ 100 million , a letter of credit sublimit of $ 200 million , and a commercial paper back-up sublimit of $ 500 million , of which $ 100 million of the swingline sublimit , $ 200 million of the letter of credit sublimit , and $ 355 million of the commercial paper back-up sublimit remained available as of december 31 , 2017. as of december 31 , 2017 , we have $ 605 million in availability under the revolving credit agreement . the revolving credit agreement is secured under our master indenture and has a term extending through july 26 , 2019. we expect to renew or replace the revolving credit agreement prior to its expiration . funds advanced under the revolving credit agreement bear interest either at a eurodollar rate or a base rate , at our option . the eurodollar rate is the libor rate for the term of the advance plus a margin ( currently 1.00 % ) based on our credit ratings .


 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 we finance our operations , working capital needs and capital expenditures from operating revenues and issuance of debt . as of december 31 , 2017 , we had $ 143.7 million in cash and cash equivalents . our committed credit arrangement as of december 31 , 2017 is as follows ( dollars in thousands ) : available authorized december 31 , amount 2017 revolving credit agreement $ 750,000 ( 1 ) $ 605,000 ( 2 ) ( 1 ) the amount of this facility that can be used to support commercial paper is limited to $ 500 million . ( 2 ) the portion of this facility that was unavailable at december 31 , 2017 was $ 145 million which was dedicated to support outstanding commercial paper . the revolving credit agreement has aggregate commitments of $ 750 million which includes a swingline sublimit of $ 100 million , a letter of credit sublimit of $ 200 million , and a commercial paper back-up sublimit of $ 500 million , of which $ 100 million of the swingline sublimit , $ 200 million of the letter of credit sublimit , and $ 355 million of the commercial paper back-up sublimit remained available as of december 31 , 2017. as of december 31 , 2017 , we have $ 605 million in availability under the revolving credit agreement . the revolving credit agreement is secured under our master indenture and has a term extending through july 26 , 2019. we expect to renew or replace the revolving credit agreement prior to its expiration . funds advanced under the revolving credit agreement bear interest either at a eurodollar rate or a base rate , at our option . the eurodollar rate is the libor rate for the term of the advance plus a margin ( currently 1.00 % ) based on our credit ratings .
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 Suspicious Activity Report : we supply and transmit our members ' electric power requirements through a portfolio of resources , including generating and transmission facilities , long‑term purchase contracts and short‑term energy purchases . we own , lease , have undivided percentage interests in , or have tolling arrangements with respect to , various generating stations . additionally , we transmit power to our members through resources that we own , lease or have undivided percentage interests in , or by wheeling power across lines owned by other transmission providers . see “ business - overview- power supply and transmission ” for a description of miles of transmission lines and substations . depending on our system requirements and contractual obligations , we are likely to both purchase and sell electric power during the same fiscal period . we purchase hydroelectric power under long‑term purchase contracts . 38 these contracts constituted our original power resource , and they remain a cost‑effective power source . we also purchase , under long‑term purchase contracts with basin , all the power which we require to serve our members ' load in the eastern interconnection and fixed scheduled quantities of power in the western interconnection . our generating facilities are located in the western interconnection and generally isolated from our members ' load in the eastern interconnection . these long‑term purchase commitments represent a majority of our electric power purchases . we purchase additional power on a long and short‑term basis , including 477 mws under long-term purchase contracts from other renewable energy resources , including wind , solar and small hydro . at the same time , we have agreed to supply electric power to non‑members . in addition , we utilize market purchases to optimize our position by routinely purchasing power when the market price is lower than our incremental production cost and routinely selling power to the short‑term market after consideration of our incremental production cost when we have excess power available above our firm commitments to both members and non‑members . we also use short-term energy purchases during periods of generation outages at our facilities . 2017 developments we , along with nine other participants , are part of an informal group known as the mwtg , which was formed to develop strategies to adapt to the changing electric industry in the rocky mountain region of the western interconnection . in january 2017 , the mwtg began discussions with the spp to explore potential membership . in september 2017 , the mwtg announced plans to commence negotiations with spp regarding membership . this announcement initiated a formal spp public stakeholder process . our negotiations with spp involve our transmission facilities , generating facilities and loads that are located in the states of colorado and wyoming , along with a small portion in western nebraska and new mexico . our membership in a regional transmission organization in the western interconnection could have many benefits for our system . each of the participating entities will have a multi-step approval process involving some combination of executive , board of director , customer , city , state , and federal approvals . approval from the ferc is also required . critical accounting policies the preparation of our financial statements in conformity with gaap requires that our management make estimates and assumptions that affect the amounts reported in our consolidated financial statements . we base these estimates and assumptions on information available as of the date of the financial statements and they are not necessarily indicative of the results to be expected for the year . we consider the following accounting policies to be critical accounting policies due to the estimation involved or due to the particular significance they have on our consolidated financial statements . accounting for rate regulation . we are a rate-regulated entity and , as a result , are subject to the accounting requirements of accounting for regulated operations . in accordance with these accounting requirements , some revenues and expenses have been deferred at the discretion of our board , which has budgetary and rate‑setting authority , if it is probable that these amounts will be refunded or recovered through future rates . regulatory assets are costs we expect to recover from members based on rates approved by our board in accordance with our rate policy . regulatory liabilities represent probable future reductions in rates associated with amounts that are expected to be refunded to members based on rates approved by our board in accordance with our rate policy . we recognize regulatory assets and liabilities as expenses or as a reduction in expenses concurrent with their recovery in rates . leases . the accounting for lease transactions in conformity with gaap requires management to make various assumptions , including the discount rate , the fair market value of the leased assets and the estimated useful life , in order to determine whether a lease should be classified as operating or capital . we are the lessor under a power sales arrangement that is required to be accounted for as an operating lease since the arrangement is in substance a lease because it conveys the right to use our power generating equipment for a stated period of time . the lease revenue from this arrangement is included in other operating revenue on our consolidated statements of operations . we are the lessee under a power purchase arrangement that is required to be accounted for as an operating lease since the arrangement is in substance a lease because it conveys to us the right to use power generating equipment for a stated period of time . it is included in lease expense on our consolidated statements of operations . 39 asset retirement obligations . we account for current obligations associated with the future retirement of tangible long‑lived assets in accordance with the accounting guidance relating to asset retirement and environmental obligations . story_separator_special_tag arrangement . operating expenses purchased power decreased 79,036 mwhs to 7,249,540 mwhs in 2017 compared to 7,328,576 mwhs in 2016. the decrease in mwhs sold was due to a decrease in short-term market purchases of 328,591 mwhs , partially offset by an increase in long-term renewable energy power purchases of 194,336 mwhs and long-term firm purchases of 55,219 mwhs . although mwhs sold decreased , purchased power expense increased $ 11.4 million to $ 339.8 million in 2017 compared to $ 328.4 million in 2016. the increase in purchased power expense was primarily due to an increase of $ 11.2 million , or 24.8 percent , to $ 56.3 million in 2017 compared to $ 45.1 million in 2016 for relatively similar mwh purchases from a new wind generating facility . our purchases of power from the new wind generating facilities had a higher average cost per mwh for the first six months of 2017 compared to the same period in 2016 when we were paying a lower pre-commercial rate . additionally , purchased power expense from basin increased in 2017 compared to 2016 for relatively similar mwh purchases from basin . our purchases of power from basin had a higher average cost per mwh in 2017 compared 2016 due to basin 's rate increase in the third quarter 2016. the increase in purchase power expense was partially offset by a decrease in short-term market purchases . depreciation , amortization and depletion expense increased $ 0.5 million to $ 174.5 million in 2017 compared to $ 174.0 million in 2016. depreciation expense for generation plant increased $ 9.9 million primarily due to the shortened life associated with the anticipated december 31 , 2022 retirement date of the nucla generating station of $ 8.8 million and due to the shortened life associated with the anticipated december 31 , 2025 retirement date of the craig station 43 unit 1 of $ 2.9 million . depreciation expense for transmission assets decreased $ 6.1 million primarily due to a $ 8.9 million decrease as a result of the transmission rate study , offset by additions of equipment throughout our transmission system . depreciation expense for general plant and other decreased $ 3.3 million primarily due to a $ 5.3 million decrease as a result of the general plant rate study , offset by additions of equipment to our general plant . other income other income decreased $ 2.0 million , or 7.1 percent , to $ 26.6 million in 2017 compared to $ 28.6 million in 2016. the decrease in other income was primarily due to the patronage allocation from basin of $ 7.1 million in 2017 compared to $ 14.4 million for the same period in 2016. the decrease was partially offset by the recognition of $ 5.0 million of deferred membership withdrawal income in 2017. year ended december 31 , 2016 compared to year ended december 31 , 2015 operating revenues member electric sales decreased 34,288 mwhs to 15,746,382 mwhs in 2016 compared to 15,780,670 mwhs in 2015. the withdrawal of kcec in june 2016 resulted in a 138,650 mwhs decrease in 2016 compared to 2015. although mwhs sold decreased in 2016 , member electric sales revenue increased $ 9.0 million to $ 1.135 billion in 2016 compared to $ 1.126 billion in 2015 as a result of the new rate design implemented for 2016. see “ - factors affecting results – rates and regulation ” for a description of our rates to our members . non‑member electric sales increased 131,534 mwhs , or 6.5 percent , to 2,158,059 mwhs in 2016 compared to 2,026,525 mwhs in 2015. the increase in mwhs sold was primarily due to 599,045 mwhs in the short-term market , offset by a decrease in firm sales of 467,511 mwhs due to the expiration of several long-term power sales arrangements in march 2016 and december 2015. although non-member electric sales increased , non-member electric sales revenue decreased $ 0.9 million to $ 119.3 million in 2016 compared to $ 120.2 million in 2015. the decrease in non-member electric sales revenue was due to a decrease in firm sales of $ 17.1 million primarily due to the expiration of several long-term power sales arrangements in march 2016 and december 2015. the decrease in non-member electric sales was partially offset by the income recognition of $ 9.2 million of previously deferred non-member electric sales revenue . this recognition in 2016 was required by our board in accordance with its budgetary and rate-setting authority . in addition , non-member electric short‑term market sales increased $ 7.0 million due to the increase in mwhs sold . other operating revenue consists primarily of wheeling , transmission and lease revenues , coal sales , and revenue from supplying steam and water to a paper manufacturer located adjacent to the escalante station . wheeling revenue is received when we charge other energy companies for transmitting electricity over our transmission lines . transmission revenue is from our membership in the spp , a regional transmission organization . the lease revenue is primarily from certain power sales arrangements that are required to be accounted for as operating leases since the arrangements are in substance leases because they convey to others the right to use power generating equipment for a stated period of time . coal sales revenue results from the sale of a portion of the coal from the colowyo mine per a contract ending in 2017 to other joint owners in the yampa project . other revenue decreased $ 2.5 million to $ 87.0 million in 2016 compared to $ 89.5 million in 2015. the decrease in other operating revenue was primarily due to a decrease in lease revenue of $ 12.6 million due to the expiration of power sales arrangements at our knutson and limon generating stations . this decrease was partially offset by a $ 7.9 million increase in transmission revenue resulting from our membership in the spp and a $ 1.1 million increase

