key components of our results of operations net sales we generate our net sales primarily from the sale of transmissions , transmission parts , support equipment , defense kits , engineering services , royalties and extended transmission coverage to a wide array of oems , distributors and the u.s. government . sales are recorded net of provisions for customer allowances and other rebates . engineering services are recorded as net sales in accordance with the terms of the contract . the associated costs are recorded in cost of sales . we also have royalty agreements with third parties that provide net sales as a result of joint efforts in developing marketable products . cost of sales our primary components of cost of sales are purchased parts , the overhead expense related to our manufacturing operations and direct labor associated with the manufacture and assembly of transmissions and parts . for the year ended december 31 , 2015 , direct material costs were approximately 68 % , overhead costs were approximately 26 % and direct labor costs were approximately 6 % of total cost of sales . we are subject to changes in our cost of sales caused by movements in underlying commodity prices . we seek to hedge against this risk by using commodity swap contracts and ltsas . see part ii , item 7a , quantitative and qualitative disclosures about market riskcommodity price risk included in this annual report on form 10-k. selling , general and administrative expenses the principal components of our selling , general and administrative expenses are salaries and benefits for our office personnel , advertising and promotional expenses , product warranty expense , expenses relating to certain information technology systems and amortization of our intangibles . engineering  research and development we incur costs in connection with research and development programs that are expected to contribute to future earnings . such costs are expensed as incurred . 33 non-gaap financial measures we use adjusted net income to measure our overall profitability because we believe it better reflects our cash flow generation by capturing the actual cash interest paid and cash taxes paid rather than our interest expense and tax expense as calculated under accounting principles generally accepted in the united states of america ( gaap ) and excludes the impact of the non-cash annual amortization of certain intangible assets and other certain non-recurring items . we use adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin , adjusted ebitda margin excluding technology-related license expenses and adjusted free cash flow to evaluate and control our cash operating costs and to measure our operating profitability . we believe the presentation of adjusted net income , adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin , adjusted ebitda margin excluding technology-related license expenses and adjusted free cash flow enhances our investors ' overall understanding of the financial performance and cash flow of our business . you should not consider adjusted net income , adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin and adjusted ebitda margin excluding technology-related license expenses as an alternative to net income , determined in accordance with gaap , as an indicator of operating performance . you should not consider adjusted free cash flow as an alternative to net cash provided by operating activities , determined in accordance with gaap , as an indicator of our cash flow . a directly comparable gaap measure to adjusted net income , adjusted ebitda and adjusted ebitda excluding technology-related license expenses is net income . a directly comparable gaap measure to adjusted free cash flow is net cash provided by operating activities . the following is a reconciliation of net income to adjusted net income , adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin and adjusted ebitda margin excluding technology-related license expenses , and a reconciliation of net cash provided by operating activities to adjusted free cash flow : replace_table_token_9_th ( a ) represents a charge associated with the impairment of our trade name as a result of lower forecasted net sales for certain of our end markets . ( b ) represents environmental remediation expenses for ongoing environmental operating , monitoring and maintenance activities at our indianapolis , indiana manufacturing facilities as a result of the epa determining that we are responsible for future operating , monitoring and maintenance activities , and that gm 's environmental remediation activities were completed in the third quarter of 2015 . ( c ) represents a charge associated with the impairment of long-lived assets related to the production of the h3000 and h4000 hybrid-propulsion systems . ( d ) represents a charge ( recorded in other expense , net ) for investments in co-development agreements to expand our position in transmission technologies . ( e ) represents fees and expenses ( recorded in other expense , net ) related to our secondary offerings in september 2014 , june 2014 , april 2014 , february 2014 , december 2013 , november 2013 and august 2013 and proposed secondary offering in april 2013 . ( f ) represents premiums and expenses related to the tender offer and redemption of allison transmission , inc. 's ( ati ) , our wholly owned subsidiary , 7.125 % senior cash pay notes due may 2019 ( 7.125 % senior notes ) . ( g ) represents adjustments ( recorded in selling , general and administrative expenses ) associated with the dual power inverter module ( dpim ) extended coverage program liability . the dpim liability will continue to be reviewed for any changes in estimates as additional claims data and field information become available . ( h ) represents losses ( recorded in other expense , net ) on the mark-to-market of our foreign currency hedge contracts and on intercompany financing transactions related to investments in plant assets for our india facility . story_separator_special_tag as a result , we do not anticipate any local liquidity restrictions to preclude us from funding our targeted expectations or operating needs with local resources . if we distribute our foreign cash balance to the u.s. or to other foreign subsidiaries , we could be required to accrue and pay u.s. taxes . for example , we would be required to accrue and pay additional u.s. taxes if we repatriate cash from certain foreign subsidiaries whose earnings we have asserted are permanently reinvested outside of the u.s. foreign earnings for which we assert permanent reinvestment outside the u.s. consists primarily of earnings of our europe and china subsidiaries . we currently do not foresee a need to repatriate earnings from these subsidiaries for which we have asserted permanent reinvestment . our liquidity requirements are significant , primarily due to our debt service requirements . in march 2015 , we commenced a cash tender offer to purchase ati 's outstanding 7.125 % senior notes . the total principal amount accepted for purchase in april 2015 was $ 420.9 million . in april 2015 , we also entered into an amendment with the term loan lenders under our senior secured credit facility to add an additional $ 470.0 million of term loans under the term b-3 loan . a portion of the proceeds from the addition to the term b-3 loan was used to purchase $ 420.9 million of the tendered 7.125 % senior notes plus accrued and unpaid interest , applicable premiums and expenses . the purchase resulted in a loss ( the premium between the purchase price of the notes and the face value of such notes ) of $ 22.7 million including deferred financing fees written off . in may 2015 , we redeemed the remaining $ 50.4 million of outstanding 7.125 % senior notes , at the redemption price equal to 103.563 % of the principal amount plus any accrued and unpaid interest , using the remaining proceeds from the additional term loans and cash on hand , resulting in a loss ( the premium between the purchase price of the notes and the face value of such notes ) of $ 2.4 million including deferred financing fees written off . in november 2015 , we entered into an amendment with the term loan lenders under our senior secured credit facility to refinance $ 189.0 million of the senior secured credit facility term b-2 loan due 2017 replacing it with an additional $ 189.0 million of term loan under the term b-3 loan . this addition to the term b-3 loan increased the debt maturity from august 2017 to august 2019 and the applicable interest rate margin at our option , is either ( a ) 2.50 % over the libor ( which may not be less than 1.00 % ) or ( b ) 1.50 % over the greater of the prime lending rate provided by the british banking association or the federal funds effective rate published by the federal reserve bank of new york . as of december 31 , 2015 , the interest rate was approximately 3.50 % on the term b-3 loan . the november 2015 amendment was treated as a modification of debt under gaap , and thus we expensed $ 0.3 million of deferred financing fees and recorded $ 1.3 million of new deferred financing fees in the consolidated financial statements . as of december 31 , 2015 , we had $ 2,402.8 million of indebtedness , all of which was associated with our term b-3 loan . our ability to make payments on and to refinance our indebtedness , and to fund planned capital expenditures will depend on our ability to generate cash in the future . this is subject to general economic , financial , competitive , legislative , regulatory and other factors that may be beyond our control . we made principal payments of $ 116.5 million , $ 157.6 million and $ 142.4 million on our long-term debt for the years ended december 31 , 2015 , 2014 and 2013 , respectively . the senior secured credit facility also provides for $ 465.0 million in revolving credit borrowings , net of an allowance for up to $ 75.0 million in outstanding letters of credit commitments . as of december 31 , 2015 , we had no outstanding borrowings on our revolving credit facility . additionally within the terms of the senior secured credit facility , a senior secured leverage ratio at or below 3.50x results in the elimination of excess cash flow payments on the senior secured credit facility for the applicable year . the senior secured credit facility provides certain financial incentives based on our total leverage ratio . a total leverage ratio at or below 4.00x results in a 25 basis point reduction to the applicable margin on our revolving credit facility , and a total leverage ratio at or below 3.50x results in a 12.5 basis point reduction to the revolving credit facility commitment fee and an additional 25 basis point reduction to the applicable margin on our revolving credit facility . a total leverage ratio at or below 3.25x results in a 25 basis point reduction to the applicable margin on our term b-3 loan . these reductions would remain in effect as long as we achieve a total leverage ratio at or below the related threshold . as of december 31 , 2015 , the total leverage ratio was 2.99x . in addition to the maximum total senior secured leverage ratio for the revolving portion of the senior secured credit facility , the senior secured credit facility includes , among other things , customary restrictions ( subject to certain exceptions ) on our ability to incur certain indebtedness or liens , make certain investments , declare or pay certain dividends or repurchase shares of our common stock . as of december 31 , 2015 , we are in compliance with all covenants

cash provided by operating activities operating activities for the year ended december 31 , 2015 generated $ 579.9 million of cash compared to $ 573.3 million for the year ended december 31 , 2014. the increase was principally driven by lower cash interest expense , lower accounts receivable commensurate with decreased net sales , and decreased excess tax benefit from stock-based compensation , partially offset by lower accounts payable , lower other liabilities , net , and higher inventories . operating activities for the year ended december 31 , 2014 generated $ 573.3 million of cash compared to $ 463.5 million for the year ended december 31 , 2013. the increase was principally driven by increased net sales , lower inventories , lower cash interest expense and higher other liabilities , net , partially offset by higher accounts receivable commensurate with increased net sales and increased excess tax benefit from stock-based compensation . cash used for investing activities investing activities for the year ended december 31 , 2015 used $ 59.7 million of cash compared to $ 67.9 million for the year ended december 31 , 2014. the decrease was principally driven by a decrease of $ 6.0 million in capital expenditures and a decrease of $ 3.9 million in investments in technology-related initiatives . the decrease in capital expenditures was principally driven by lower product initiatives spending . investing activities for the year ended december 31 , 2014 used $ 67.9 million of cash compared to $ 81.5 million for the year ended december 31 , 2013. the decrease was principally driven by a decrease of $ 10.3 million in capital expenditures and a decrease of $ 3.0 million in investments in technology-related initiatives . the decrease in capital expenditures was principally driven by lower product initiatives spending , partially offset by increased investments in productivity and replacement programs .


 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.
     ```cash provided by operating activities operating activities for the year ended december 31 , 2015 generated $ 579.9 million of cash compared to $ 573.3 million for the year ended december 31 , 2014. the increase was principally driven by lower cash interest expense , lower accounts receivable commensurate with decreased net sales , and decreased excess tax benefit from stock-based compensation , partially offset by lower accounts payable , lower other liabilities , net , and higher inventories . operating activities for the year ended december 31 , 2014 generated $ 573.3 million of cash compared to $ 463.5 million for the year ended december 31 , 2013. the increase was principally driven by increased net sales , lower inventories , lower cash interest expense and higher other liabilities , net , partially offset by higher accounts receivable commensurate with increased net sales and increased excess tax benefit from stock-based compensation . cash used for investing activities investing activities for the year ended december 31 , 2015 used $ 59.7 million of cash compared to $ 67.9 million for the year ended december 31 , 2014. the decrease was principally driven by a decrease of $ 6.0 million in capital expenditures and a decrease of $ 3.9 million in investments in technology-related initiatives . the decrease in capital expenditures was principally driven by lower product initiatives spending . investing activities for the year ended december 31 , 2014 used $ 67.9 million of cash compared to $ 81.5 million for the year ended december 31 , 2013. the decrease was principally driven by a decrease of $ 10.3 million in capital expenditures and a decrease of $ 3.0 million in investments in technology-related initiatives . the decrease in capital expenditures was principally driven by lower product initiatives spending , partially offset by increased investments in productivity and replacement programs .
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 Suspicious Activity Report : key components of our results of operations net sales we generate our net sales primarily from the sale of transmissions , transmission parts , support equipment , defense kits , engineering services , royalties and extended transmission coverage to a wide array of oems , distributors and the u.s. government . sales are recorded net of provisions for customer allowances and other rebates . engineering services are recorded as net sales in accordance with the terms of the contract . the associated costs are recorded in cost of sales . we also have royalty agreements with third parties that provide net sales as a result of joint efforts in developing marketable products . cost of sales our primary components of cost of sales are purchased parts , the overhead expense related to our manufacturing operations and direct labor associated with the manufacture and assembly of transmissions and parts . for the year ended december 31 , 2015 , direct material costs were approximately 68 % , overhead costs were approximately 26 % and direct labor costs were approximately 6 % of total cost of sales . we are subject to changes in our cost of sales caused by movements in underlying commodity prices . we seek to hedge against this risk by using commodity swap contracts and ltsas . see part ii , item 7a , quantitative and qualitative disclosures about market riskcommodity price risk included in this annual report on form 10-k. selling , general and administrative expenses the principal components of our selling , general and administrative expenses are salaries and benefits for our office personnel , advertising and promotional expenses , product warranty expense , expenses relating to certain information technology systems and amortization of our intangibles . engineering  research and development we incur costs in connection with research and development programs that are expected to contribute to future earnings . such costs are expensed as incurred . 33 non-gaap financial measures we use adjusted net income to measure our overall profitability because we believe it better reflects our cash flow generation by capturing the actual cash interest paid and cash taxes paid rather than our interest expense and tax expense as calculated under accounting principles generally accepted in the united states of america ( gaap ) and excludes the impact of the non-cash annual amortization of certain intangible assets and other certain non-recurring items . we use adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin , adjusted ebitda margin excluding technology-related license expenses and adjusted free cash flow to evaluate and control our cash operating costs and to measure our operating profitability . we believe the presentation of adjusted net income , adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin , adjusted ebitda margin excluding technology-related license expenses and adjusted free cash flow enhances our investors ' overall understanding of the financial performance and cash flow of our business . you should not consider adjusted net income , adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin and adjusted ebitda margin excluding technology-related license expenses as an alternative to net income , determined in accordance with gaap , as an indicator of operating performance . you should not consider adjusted free cash flow as an alternative to net cash provided by operating activities , determined in accordance with gaap , as an indicator of our cash flow . a directly comparable gaap measure to adjusted net income , adjusted ebitda and adjusted ebitda excluding technology-related license expenses is net income . a directly comparable gaap measure to adjusted free cash flow is net cash provided by operating activities . the following is a reconciliation of net income to adjusted net income , adjusted ebitda , adjusted ebitda excluding technology-related license expenses , adjusted ebitda margin and adjusted ebitda margin excluding technology-related license expenses , and a reconciliation of net cash provided by operating activities to adjusted free cash flow : replace_table_token_9_th ( a ) represents a charge associated with the impairment of our trade name as a result of lower forecasted net sales for certain of our end markets . ( b ) represents environmental remediation expenses for ongoing environmental operating , monitoring and maintenance activities at our indianapolis , indiana manufacturing facilities as a result of the epa determining that we are responsible for future operating , monitoring and maintenance activities , and that gm 's environmental remediation activities were completed in the third quarter of 2015 . ( c ) represents a charge associated with the impairment of long-lived assets related to the production of the h3000 and h4000 hybrid-propulsion systems . ( d ) represents a charge ( recorded in other expense , net ) for investments in co-development agreements to expand our position in transmission technologies . ( e ) represents fees and expenses ( recorded in other expense , net ) related to our secondary offerings in september 2014 , june 2014 , april 2014 , february 2014 , december 2013 , november 2013 and august 2013 and proposed secondary offering in april 2013 . ( f ) represents premiums and expenses related to the tender offer and redemption of allison transmission , inc. 's ( ati ) , our wholly owned subsidiary , 7.125 % senior cash pay notes due may 2019 ( 7.125 % senior notes ) . ( g ) represents adjustments ( recorded in selling , general and administrative expenses ) associated with the dual power inverter module ( dpim ) extended coverage program liability . the dpim liability will continue to be reviewed for any changes in estimates as additional claims data and field information become available . ( h ) represents losses ( recorded in other expense , net ) on the mark-to-market of our foreign currency hedge contracts and on intercompany financing transactions related to investments in plant assets for our india facility . story_separator_special_tag as a result , we do not anticipate any local liquidity restrictions to preclude us from funding our targeted expectations or operating needs with local resources . if we distribute our foreign cash balance to the u.s. or to other foreign subsidiaries , we could be required to accrue and pay u.s. taxes . for example , we would be required to accrue and pay additional u.s. taxes if we repatriate cash from certain foreign subsidiaries whose earnings we have asserted are permanently reinvested outside of the u.s. foreign earnings for which we assert permanent reinvestment outside the u.s. consists primarily of earnings of our europe and china subsidiaries . we currently do not foresee a need to repatriate earnings from these subsidiaries for which we have asserted permanent reinvestment . our liquidity requirements are significant , primarily due to our debt service requirements . in march 2015 , we commenced a cash tender offer to purchase ati 's outstanding 7.125 % senior notes . the total principal amount accepted for purchase in april 2015 was $ 420.9 million . in april 2015 , we also entered into an amendment with the term loan lenders under our senior secured credit facility to add an additional $ 470.0 million of term loans under the term b-3 loan . a portion of the proceeds from the addition to the term b-3 loan was used to purchase $ 420.9 million of the tendered 7.125 % senior notes plus accrued and unpaid interest , applicable premiums and expenses . the purchase resulted in a loss ( the premium between the purchase price of the notes and the face value of such notes ) of $ 22.7 million including deferred financing fees written off . in may 2015 , we redeemed the remaining $ 50.4 million of outstanding 7.125 % senior notes , at the redemption price equal to 103.563 % of the principal amount plus any accrued and unpaid interest , using the remaining proceeds from the additional term loans and cash on hand , resulting in a loss ( the premium between the purchase price of the notes and the face value of such notes ) of $ 2.4 million including deferred financing fees written off . in november 2015 , we entered into an amendment with the term loan lenders under our senior secured credit facility to refinance $ 189.0 million of the senior secured credit facility term b-2 loan due 2017 replacing it with an additional $ 189.0 million of term loan under the term b-3 loan . this addition to the term b-3 loan increased the debt maturity from august 2017 to august 2019 and the applicable interest rate margin at our option , is either ( a ) 2.50 % over the libor ( which may not be less than 1.00 % ) or ( b ) 1.50 % over the greater of the prime lending rate provided by the british banking association or the federal funds effective rate published by the federal reserve bank of new york . as of december 31 , 2015 , the interest rate was approximately 3.50 % on the term b-3 loan . the november 2015 amendment was treated as a modification of debt under gaap , and thus we expensed $ 0.3 million of deferred financing fees and recorded $ 1.3 million of new deferred financing fees in the consolidated financial statements . as of december 31 , 2015 , we had $ 2,402.8 million of indebtedness , all of which was associated with our term b-3 loan . our ability to make payments on and to refinance our indebtedness , and to fund planned capital expenditures will depend on our ability to generate cash in the future . this is subject to general economic , financial , competitive , legislative , regulatory and other factors that may be beyond our control . we made principal payments of $ 116.5 million , $ 157.6 million and $ 142.4 million on our long-term debt for the years ended december 31 , 2015 , 2014 and 2013 , respectively . the senior secured credit facility also provides for $ 465.0 million in revolving credit borrowings , net of an allowance for up to $ 75.0 million in outstanding letters of credit commitments . as of december 31 , 2015 , we had no outstanding borrowings on our revolving credit facility . additionally within the terms of the senior secured credit facility , a senior secured leverage ratio at or below 3.50x results in the elimination of excess cash flow payments on the senior secured credit facility for the applicable year . the senior secured credit facility provides certain financial incentives based on our total leverage ratio . a total leverage ratio at or below 4.00x results in a 25 basis point reduction to the applicable margin on our revolving credit facility , and a total leverage ratio at or below 3.50x results in a 12.5 basis point reduction to the revolving credit facility commitment fee and an additional 25 basis point reduction to the applicable margin on our revolving credit facility . a total leverage ratio at or below 3.25x results in a 25 basis point reduction to the applicable margin on our term b-3 loan . these reductions would remain in effect as long as we achieve a total leverage ratio at or below the related threshold . as of december 31 , 2015 , the total leverage ratio was 2.99x . in addition to the maximum total senior secured leverage ratio for the revolving portion of the senior secured credit facility , the senior secured credit facility includes , among other things , customary restrictions ( subject to certain exceptions ) on our ability to incur certain indebtedness or liens , make certain investments , declare or pay certain dividends or repurchase shares of our common stock . as of december 31 , 2015 , we are in compliance with all covenants

