in our u.s. drilling operating segment , our rig years ( a measure of activity and utilization ) have decreased from 212.5 years during fiscal year 2014 to 120.0 years during fiscal year 2015. in our canada drilling operating segment , our rig years have declined by roughly 51 % from 2014. our international operating segment has not been immune from the impact of lower oil prices . although international drilling markets tend to react slower than the north american markets , we began to experience downward pressure on dayrates in the international segment beginning in the second quarter of 2015. our international rig years declined in the latter half of 2015 , primarily due to the conclusion of several drilling projects as well as reduced activity resulting from lower commodity prices . given the commodity price environment entering 2016 , we expect continued erosion at least through the first half of the year in industry rig counts , both domestic and international , as well as continued downward pressure on the utilization and pricing of 23 our rig fleets . at december 31 , 2015 , we had $ 2.24 billion availability remaining under our $ 2.25 billion revolving credit facility and commercial paper program , which expires july 2020. availability under the revolving credit facility is subject to a covenant not to exceed a net debt to capital ratio of 0.60:1. as of december 31 , 2015 , our net debt to capital ratio was 0.44:1. see item 6 . selected financial data . financial results during 2015 , our income ( loss ) from continuing operations was adversely affected by approximately $ 369.0 million in impairments and other charges . net loss from continuing operations totaled $ 329.5 million for 2015 ( $ 1.14 per diluted share ) compared to a net loss from continuing operations of $ 669.3 million ( $ 2.28 per diluted share ) in 2014. the impairment charges stemmed from the impact of the industry downturn on our business activity and future outlook as the continuation of depressed oil prices led to considerable reductions in capital spending by some of our customers and diminished demand for our drilling services . the impairments and retirement provisions were primarily comprised of $ 140.1 million related to tangible assets and equipment and $ 180.6 million related to an other-than-temporary impairment on our equity method investment in cjes . operating revenues in 2015 totaled $ 3.9 billion , representing a decrease of $ 2.9 billion , or 43 % , over 2014. the decrease in revenues was due in part to ceasing to consolidate the revenues associated with our completion & production services business . further exacerbating the decline in revenues was the decrease in activity and reduced dayrates within our u.s. and canada drilling operating segments resulting from the overall decline in oil prices throughout 2015 as mentioned above . these decreases were partially offset by an increase in revenue in our international drilling operating segment . during 2014 , our income ( loss ) from continuing operations was adversely affected by approximately $ 1.03 billion in impairments and other charges . net loss from continuing operations totaled $ 669.3 million for 2014 ( $ 2.28 per diluted share ) compared to net income from continuing operations of $ 158.3 million ( $ 0.51 per diluted share ) in 2013. the impairments and retirement provisions stemmed from the sharp decline in crude oil prices during the fourth quarter of 2014 and the resulting impact on our customers ' spending programs and demand for our services . the impairments and retirement provisions were comprised of approximately $ 611.6 million in charges related to drilling rigs and rig equipment and $ 386.5 million in impairments to our goodwill and intangible assets . the goodwill and intangible assets were primarily attributable to our completion services operating segment from the acquisition of superior well services , inc. ( superior ) in 2010. of the $ 611.6 million in charges related to our drilling rigs and rig equipment , the majority is attributable to retirements and impairments to our lower 48 legacy rig fleet ( non ac rigs ) , including the functional retirement of 25 mechanical rigs , an impairment to the scr fleet and the resultant reduction in yard assets and spare rig components due to reduced operating fleet size . the balance is attributable to charges for the impairment or retirement of our jackup rig fleet in the gulf of mexico , our coil tubing drilling rigs in canada and various other under-utilized rigs and related equipment in canada and our international markets . excluding these items , our operating results increased in 2014 over 2013. operating revenues in 2014 totaled $ 6.8 billion , representing an increase of $ 652.2 million , or 11 % , over 2013. the increase in revenues was driven by increases from virtually all of our operating segments with the exception of canada drilling . adjusted operating income for 2014 totaled $ 604.3 million , representing an increase of $ 46.1 million , or 8 % , over 2013. this increase was driven primarily by our u.s. and international drilling and rig services operating segments , which more than offset declines in our completion and production services and canada drilling operating segments . 24 the following tables set forth certain information with respect to our reportable segments and rig activity : replace_table_token_8_th 25 replace_table_token_9_th replace_table_token_10_th ( 1 ) all periods present the operating activities of most of our wholly owned oil and gas businesses , aircraft logistics operations and construction services as discontinued operations . ( 2 ) includes our other services comprised of our drilling technology and top drive manufacturing , directional drilling , rig instrumentation and software services . ( 3 ) represents the elimination of inter-segment transactions . story_separator_special_tag should it remain at these levels for an extended period of time , it could result in a future other-than-temporary impairment . provision for international operations during 2015 , we recognized $ 25.4 million related to assets and receivables impacted by the degradation of the overall country economy and financial situation in venezuela , which has been adversely affected by the downturn in oil prices , primarily comprised of a loss of $ 10.0 million related to the remeasurement of our net monetary assets denominated in local currency from the official exchange rate of 6.3 bolivares per us dollar to the simadi exchange rate which was 199 bolivares per us dollar as of september 30 , 2015 and $ 15.4 million related to the write-off of a receivable balance . the balance of this provision represents an obligation associated with the decision to exit a non-core business line in another country within the region of $ 22.9 million . for the year ended december 31 , 2014 tangible assets and equipment the following table summarizes the 2014 retirement and impairment charges for tangible assets and equipment by operating segment : 32 replace_table_token_15_th approximately two-thirds of the 2014 charges from drilling rigs and rig equipment is related to the u.s. lower 48 legacy rig fleet . given the sharp decline in crude oil prices and the resulting impact on our customers ' spending programs that we experienced in 2014 , and the disproportionate impact of the reduced activity that we believe our legacy rig fleet will absorb , we have retired 25 mechanical rigs and impaired our fleet of scr rigs , including the resultant retirement of and reduction in yard assets and spare rig components associated with a reduced overall size of our working rig fleet . also included in the 2014 charges for our u.s. drilling rigs and rig equipment is a retirement provision of approximately $ 54.4 million for our gulf of mexico jackup fleet . this market has been challenged for the past several years and we believe the drop in oil prices will exacerbate the lack of demand for these rigs . the majority of these rigs would require substantial amounts of capital in order for them to be operable again . the balance of the drilling rigs and rig equipment charges relate to our coil tubing drilling rig fleet in canada and various under-utilized or under-performing rigs or asset classes throughout our international and canada drilling fleets . we also recognized an impairment charge related to obsolete inventory within our rig services operating segment . goodwill and intangible assets during 2014 , we recognized an impairment of goodwill totaling $ 356.6 million , the majority of which was for the remaining goodwill balance of $ 335.0 million in our completion services operating segment related to the acquisition of superior in 2010. the value attributable to the merger with cjes declined sharply beginning in the fourth quarter of 2014 , with a drop in the market price of cjes 's stock and the agreed upon reduction to the amount of cash we expect to receive from this transaction . the combination of these events and a sharp decline in the market price of our stock , led us to believe that a triggering event had occurred in the fourth quarter of 2014 , and we performed an impairment test on our remaining goodwill balances . we determined that our completion services goodwill balances should be fully impaired . the balance of the impairment relates to $ 21.6 million in goodwill related to ryan directional services , inc. our directional drilling operations included in our rig services operating segment . the decline in oil prices and the impact it had on our businesses , along with the lack of certainty surrounding an eventual recovery , led us to impair these goodwill balances . additionally , during 2014 , we recognized an impairment of $ 29.9 million primarily related to various intangible assets , such as customer relationships within our completion & production services and rig services operating segments related to previous acquisitions . transaction costs during 2014 , we incurred $ 22.3 million in transaction costs related to the merger with cjes , including professional fees and other costs incurred to reorganize the business in contemplation of the merger . other-than-temporary impairment during 2014 , we recorded an other-than-temporary impairment of $ 7.0 million related to an equity security . because the trading price of this security remained below our cost basis for an extended period , we determined the investment was other than temporarily impaired and it was appropriate to write down the investment 's carrying value to its current estimated fair value . 33 for the year ended december 31 , 2013 provision for retirement of long-lived assets during 2013 , we recorded a provision for retirement of long-lived assets in multiple operating segments totaling $ 14.0 million , which reduced the carrying value of some assets to their salvage value . the retirements related to assets in saudi arabia and included obsolete top-drives , nonworking trucks , generators , engines and other miscellaneous equipment . the retirements in our canada operations included functionally inoperable rigs and other drilling equipment . in our completion & production services operations , the retirements related to rigs and vehicles that would require significant repair to return to work and other non-core assets . impairments of long-lived assets during 2013 , we recognized an impairment of $ 20.0 million to our fleet of coil-tubing units in our completion & production services business . intense competition and oversupply of equipment has led to lower utilization and margins for this product line . when these factors were considered as part of our annual impairment tests on long-lived assets , the sum of the estimated future cash flows , on an undiscounted basis , was less than the carrying amount of these assets . the estimated fair values of these assets were

financial condition and sources of liquidity our primary sources of liquidity are cash and investments , availability under our revolving credit facility , our commercial paper program and cash generated from operations . as of december 31 , 2015 , we had cash and short-term investments of $ 274.6 million and working capital of $ 0.5 billion . as of december 31 , 2014 , we had cash and short-term investments of $ 536.2 million and working capital of $ 1.2 billion . at december 31 , 2015 , we had $ 2.24 billion availability remaining under our $ 2.25 billion revolving credit facility and commercial paper program . during 2015 , we entered into an amendment to our existing committed , unsecured revolving credit facility to increase the borrowing capacity to $ 2.2 billion , extend the maturity date to july 2020 and increase the size of the accordion option to 38 $ 500.0 million . we subsequently exercised $ 50.0 million of the accordion option to bring the total availability to $ 2.25 billion . we expect to use this capacity to provide financial flexibility for strategic investment opportunities , debt refinancing and other corporate uses . a dditionally , nabors industries , inc. , our wholly owned subsidiary , entered into a new five-year unsecured term loan facility for $ 325.0 million . the term loan facility contains a mandatory prepayment of $ 162.5 million due in 2018. we used this facility to pay down our commercial paper borrowings during 2015. we had 11 letter-of-credit facilities with various banks as of december 31 , 2015. availability under these facilities as of december 31 , 2015 was as follows : ( in thousands ) credit available $ 657,239 letters of credit outstanding , inclusive of financial and performance guarantees 211,685 remaining availability $ 445,554 our ability to access capital markets or to otherwise obtain sufficient financing is enhanced by our senior unsecured debt ratings as provided by the major credit rating agencies in the united states and our historical ability to access these markets as needed .


 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.
     ```financial condition and sources of liquidity our primary sources of liquidity are cash and investments , availability under our revolving credit facility , our commercial paper program and cash generated from operations . as of december 31 , 2015 , we had cash and short-term investments of $ 274.6 million and working capital of $ 0.5 billion . as of december 31 , 2014 , we had cash and short-term investments of $ 536.2 million and working capital of $ 1.2 billion . at december 31 , 2015 , we had $ 2.24 billion availability remaining under our $ 2.25 billion revolving credit facility and commercial paper program . during 2015 , we entered into an amendment to our existing committed , unsecured revolving credit facility to increase the borrowing capacity to $ 2.2 billion , extend the maturity date to july 2020 and increase the size of the accordion option to 38 $ 500.0 million . we subsequently exercised $ 50.0 million of the accordion option to bring the total availability to $ 2.25 billion . we expect to use this capacity to provide financial flexibility for strategic investment opportunities , debt refinancing and other corporate uses . a dditionally , nabors industries , inc. , our wholly owned subsidiary , entered into a new five-year unsecured term loan facility for $ 325.0 million . the term loan facility contains a mandatory prepayment of $ 162.5 million due in 2018. we used this facility to pay down our commercial paper borrowings during 2015. we had 11 letter-of-credit facilities with various banks as of december 31 , 2015. availability under these facilities as of december 31 , 2015 was as follows : ( in thousands ) credit available $ 657,239 letters of credit outstanding , inclusive of financial and performance guarantees 211,685 remaining availability $ 445,554 our ability to access capital markets or to otherwise obtain sufficient financing is enhanced by our senior unsecured debt ratings as provided by the major credit rating agencies in the united states and our historical ability to access these markets as needed .
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 Suspicious Activity Report : in our u.s. drilling operating segment , our rig years ( a measure of activity and utilization ) have decreased from 212.5 years during fiscal year 2014 to 120.0 years during fiscal year 2015. in our canada drilling operating segment , our rig years have declined by roughly 51 % from 2014. our international operating segment has not been immune from the impact of lower oil prices . although international drilling markets tend to react slower than the north american markets , we began to experience downward pressure on dayrates in the international segment beginning in the second quarter of 2015. our international rig years declined in the latter half of 2015 , primarily due to the conclusion of several drilling projects as well as reduced activity resulting from lower commodity prices . given the commodity price environment entering 2016 , we expect continued erosion at least through the first half of the year in industry rig counts , both domestic and international , as well as continued downward pressure on the utilization and pricing of 23 our rig fleets . at december 31 , 2015 , we had $ 2.24 billion availability remaining under our $ 2.25 billion revolving credit facility and commercial paper program , which expires july 2020. availability under the revolving credit facility is subject to a covenant not to exceed a net debt to capital ratio of 0.60:1. as of december 31 , 2015 , our net debt to capital ratio was 0.44:1. see item 6 . selected financial data . financial results during 2015 , our income ( loss ) from continuing operations was adversely affected by approximately $ 369.0 million in impairments and other charges . net loss from continuing operations totaled $ 329.5 million for 2015 ( $ 1.14 per diluted share ) compared to a net loss from continuing operations of $ 669.3 million ( $ 2.28 per diluted share ) in 2014. the impairment charges stemmed from the impact of the industry downturn on our business activity and future outlook as the continuation of depressed oil prices led to considerable reductions in capital spending by some of our customers and diminished demand for our drilling services . the impairments and retirement provisions were primarily comprised of $ 140.1 million related to tangible assets and equipment and $ 180.6 million related to an other-than-temporary impairment on our equity method investment in cjes . operating revenues in 2015 totaled $ 3.9 billion , representing a decrease of $ 2.9 billion , or 43 % , over 2014. the decrease in revenues was due in part to ceasing to consolidate the revenues associated with our completion & production services business . further exacerbating the decline in revenues was the decrease in activity and reduced dayrates within our u.s. and canada drilling operating segments resulting from the overall decline in oil prices throughout 2015 as mentioned above . these decreases were partially offset by an increase in revenue in our international drilling operating segment . during 2014 , our income ( loss ) from continuing operations was adversely affected by approximately $ 1.03 billion in impairments and other charges . net loss from continuing operations totaled $ 669.3 million for 2014 ( $ 2.28 per diluted share ) compared to net income from continuing operations of $ 158.3 million ( $ 0.51 per diluted share ) in 2013. the impairments and retirement provisions stemmed from the sharp decline in crude oil prices during the fourth quarter of 2014 and the resulting impact on our customers ' spending programs and demand for our services . the impairments and retirement provisions were comprised of approximately $ 611.6 million in charges related to drilling rigs and rig equipment and $ 386.5 million in impairments to our goodwill and intangible assets . the goodwill and intangible assets were primarily attributable to our completion services operating segment from the acquisition of superior well services , inc. ( superior ) in 2010. of the $ 611.6 million in charges related to our drilling rigs and rig equipment , the majority is attributable to retirements and impairments to our lower 48 legacy rig fleet ( non ac rigs ) , including the functional retirement of 25 mechanical rigs , an impairment to the scr fleet and the resultant reduction in yard assets and spare rig components due to reduced operating fleet size . the balance is attributable to charges for the impairment or retirement of our jackup rig fleet in the gulf of mexico , our coil tubing drilling rigs in canada and various other under-utilized rigs and related equipment in canada and our international markets . excluding these items , our operating results increased in 2014 over 2013. operating revenues in 2014 totaled $ 6.8 billion , representing an increase of $ 652.2 million , or 11 % , over 2013. the increase in revenues was driven by increases from virtually all of our operating segments with the exception of canada drilling . adjusted operating income for 2014 totaled $ 604.3 million , representing an increase of $ 46.1 million , or 8 % , over 2013. this increase was driven primarily by our u.s. and international drilling and rig services operating segments , which more than offset declines in our completion and production services and canada drilling operating segments . 24 the following tables set forth certain information with respect to our reportable segments and rig activity : replace_table_token_8_th 25 replace_table_token_9_th replace_table_token_10_th ( 1 ) all periods present the operating activities of most of our wholly owned oil and gas businesses , aircraft logistics operations and construction services as discontinued operations . ( 2 ) includes our other services comprised of our drilling technology and top drive manufacturing , directional drilling , rig instrumentation and software services . ( 3 ) represents the elimination of inter-segment transactions . story_separator_special_tag should it remain at these levels for an extended period of time , it could result in a future other-than-temporary impairment . provision for international operations during 2015 , we recognized $ 25.4 million related to assets and receivables impacted by the degradation of the overall country economy and financial situation in venezuela , which has been adversely affected by the downturn in oil prices , primarily comprised of a loss of $ 10.0 million related to the remeasurement of our net monetary assets denominated in local currency from the official exchange rate of 6.3 bolivares per us dollar to the simadi exchange rate which was 199 bolivares per us dollar as of september 30 , 2015 and $ 15.4 million related to the write-off of a receivable balance . the balance of this provision represents an obligation associated with the decision to exit a non-core business line in another country within the region of $ 22.9 million . for the year ended december 31 , 2014 tangible assets and equipment the following table summarizes the 2014 retirement and impairment charges for tangible assets and equipment by operating segment : 32 replace_table_token_15_th approximately two-thirds of the 2014 charges from drilling rigs and rig equipment is related to the u.s. lower 48 legacy rig fleet . given the sharp decline in crude oil prices and the resulting impact on our customers ' spending programs that we experienced in 2014 , and the disproportionate impact of the reduced activity that we believe our legacy rig fleet will absorb , we have retired 25 mechanical rigs and impaired our fleet of scr rigs , including the resultant retirement of and reduction in yard assets and spare rig components associated with a reduced overall size of our working rig fleet . also included in the 2014 charges for our u.s. drilling rigs and rig equipment is a retirement provision of approximately $ 54.4 million for our gulf of mexico jackup fleet . this market has been challenged for the past several years and we believe the drop in oil prices will exacerbate the lack of demand for these rigs . the majority of these rigs would require substantial amounts of capital in order for them to be operable again . the balance of the drilling rigs and rig equipment charges relate to our coil tubing drilling rig fleet in canada and various under-utilized or under-performing rigs or asset classes throughout our international and canada drilling fleets . we also recognized an impairment charge related to obsolete inventory within our rig services operating segment . goodwill and intangible assets during 2014 , we recognized an impairment of goodwill totaling $ 356.6 million , the majority of which was for the remaining goodwill balance of $ 335.0 million in our completion services operating segment related to the acquisition of superior in 2010. the value attributable to the merger with cjes declined sharply beginning in the fourth quarter of 2014 , with a drop in the market price of cjes 's stock and the agreed upon reduction to the amount of cash we expect to receive from this transaction . the combination of these events and a sharp decline in the market price of our stock , led us to believe that a triggering event had occurred in the fourth quarter of 2014 , and we performed an impairment test on our remaining goodwill balances . we determined that our completion services goodwill balances should be fully impaired . the balance of the impairment relates to $ 21.6 million in goodwill related to ryan directional services , inc. our directional drilling operations included in our rig services operating segment . the decline in oil prices and the impact it had on our businesses , along with the lack of certainty surrounding an eventual recovery , led us to impair these goodwill balances . additionally , during 2014 , we recognized an impairment of $ 29.9 million primarily related to various intangible assets , such as customer relationships within our completion & production services and rig services operating segments related to previous acquisitions . transaction costs during 2014 , we incurred $ 22.3 million in transaction costs related to the merger with cjes , including professional fees and other costs incurred to reorganize the business in contemplation of the merger . other-than-temporary impairment during 2014 , we recorded an other-than-temporary impairment of $ 7.0 million related to an equity security . because the trading price of this security remained below our cost basis for an extended period , we determined the investment was other than temporarily impaired and it was appropriate to write down the investment 's carrying value to its current estimated fair value . 33 for the year ended december 31 , 2013 provision for retirement of long-lived assets during 2013 , we recorded a provision for retirement of long-lived assets in multiple operating segments totaling $ 14.0 million , which reduced the carrying value of some assets to their salvage value . the retirements related to assets in saudi arabia and included obsolete top-drives , nonworking trucks , generators , engines and other miscellaneous equipment . the retirements in our canada operations included functionally inoperable rigs and other drilling equipment . in our completion & production services operations , the retirements related to rigs and vehicles that would require significant repair to return to work and other non-core assets . impairments of long-lived assets during 2013 , we recognized an impairment of $ 20.0 million to our fleet of coil-tubing units in our completion & production services business . intense competition and oversupply of equipment has led to lower utilization and margins for this product line . when these factors were considered as part of our annual impairment tests on long-lived assets , the sum of the estimated future cash flows , on an undiscounted basis , was less than the carrying amount of these assets . the estimated fair values of these assets were

