operating expenses operations and maintenance o & m expenses include interconnection costs , labor expenses , turbine servicing costs , land payments , insurance , materials , supplies , shared services and administrative expenses attributable to nep 's projects , and costs and expenses under the msa , asas and o & m agreements ( see note 13 ) . o & m expenses also include the cost of maintaining and replacing certain parts for the projects in the portfolio to maintain , over the long term , operating income or operating capacity . o & m expenses increased $ 9 million during the year ended december 31 , 2018 primarily due to an increase of approximately $ 12 million in idr fees related to growth in nep 's distributions to its common unitholders and increases in o & m expenses at various projects , partly offset by a decrease of approximately $ 8 million as a result of the sale of canadian holdings . 41 o & m expenses related to the existing portfolio are expected to remain relatively stable from year to year . however , nep 's o & m expenses are likely to increase as nep acquires new projects . depreciation and amortization depreciation and amortization expense reflects costs associated with depreciation and amortization of nep 's assets , based on depreciable asset lives and consistent depreciation methodologies . for certain of the renewable energy projects , citcs have been elected and are recorded as a reduction in property , plant and equipment - net on the consolidated balance sheets and amortized as a reduction to depreciation and amortization expense over the estimated life of the related property . depreciation and amortization expense also includes a provision for wind and solar facility dismantlement , asset removal costs and accretion related to asset retirement obligations and the amortization of finite-lived intangible assets . depreciation and amortization expense decreased $ 23 million during the year ended december 31 , 2018 primarily as a result of the sale of canadian holdings . gain on disposal of canadian holdings during the year ended december 31 , 2018 , a subsidiary of nep completed the sale of canadian holdings and nep recognized a pre-tax gain of approximately $ 153 million . see note 2 - disposal of canadian holdings . other income ( deductions ) interest expense interest expense primarily consists of interest under long-term debt agreements and mark-to-market gains and losses on interest rate contracts . interest expense increased approximately $ 49 million during the year ended december 31 , 2018 primarily due to unfavorable mark-to-market activity of $ 56 million , partly offset by a decrease of $ 13 million in interest expense associated with the sale of canadian holdings . benefits associated with differential membership interests - net for the year ended december 31 , 2017 , benefits associated with differential membership interests - net reflects benefits recognized by nep as third-party investors received their portion of the economic attributes , including income tax attributes , of the underlying wind projects , net of associated costs . nep recognized income related to differential membership interests of approximately $ 370 million for the year ended december 31 , 2018 which , due to the adoption of an accounting standards update , is reflected as a loss attributable to noncontrolling interests in the consolidated statements of income , of which approximately $ 231 million related to the change in federal corporate income tax rates that became effective january 1 , 2018. see note 2 - differential membership interests . approximately $ 240 million of the loss attributable to differential membership interests relates to nee 's noncontrolling interest and $ 130 million is reflected as net income attributable to nep . other - net the increase in other - net for the year ended december 31 , 2018 primarily reflects an approximately $ 17 million increase related to 2018 gains on foreign currency exchange contracts ( see note 7 ) and the difference between the total net identifiable assets at fair value and the total consideration transferred for an acquisition in december 2018 ( see note 3 ) . income taxes for periods through december 31 , 2017 , when nep acquired a neer project , income taxes were calculated on the predecessor method using the separate return method applied to the group of renewable energy projects acquired . as a result of the governance changes discussed in note 3 , beginning in january 1 , 2018 , acquisitions from neer are no longer treated as common control acquisitions , and income taxes are calculated on the successor method under which taxes are calculated for nep as a single taxpaying corporation for u.s. federal and state income taxes ( based on its election to be taxed as a corporation ) . because nep opco is a limited partnership , nep only recognizes in income its applicable ownership share of u.s. income taxes related to the u.s. projects and , prior to the sale of canadian holdings , the canadian projects . nep 's former canadian subsidiaries were all canadian taxpayers , and therefore nep recognized in income all of the canadian taxes . income taxes include nep 's applicable ownership share of u.s. taxes and 100 % of canadian taxes . net income or loss attributable to noncontrolling interests includes no u.s. taxes and neer 's applicable ownership share of canadian taxes . net income attributable to nep includes nep 's applicable ownership share of u.s. and canadian taxes . for the year ended december 31 , 2018 , nep recorded income tax expense of approximately $ 6 million on income before income taxes of $ 273 million , resulting in an effective tax rate of approximately 2 % . story_separator_special_tag no u.s. income taxes were provided with regard to these entities for periods prior to the nep acquisition date . see note 5 . impairment of long-lived assets nep evaluates long-lived assets , including finite-lived intangible assets , for impairment when events or changes in circumstances indicate that the carrying amount may not be recoverable . an impairment loss is required to be recognized if the carrying value of the asset exceeds the undiscounted future net cash flows associated with that asset . the impairment loss to be recognized is the amount by which the carrying value of the long-lived asset exceeds the asset 's fair value . in most instances , the fair value is determined by discounting estimated future cash flows using an appropriate interest rate . the amount of future net cash flows , the timing of such cash flows and the determination of an appropriate interest rate all involve estimates and judgments about future events . in particular , the aggregate amount of cash flows determines whether an impairment exists , and the timing of the cash flows is critical in determining fair value for the purposes of determining the impairment loss to be recognized . because each assessment is based on the facts and circumstances associated with each long-lived asset , the effects of changes in assumptions can not be generalized . see note 15 - pg & e bankruptcy for a discussion of an impairment analysis related to the pg & e bankruptcy filing . business combinations certain assumptions and estimates are employed in determining the fair value of assets acquired , evaluating the fair value of liabilities assumed , as well as in determining the allocation of goodwill to a reporting unit . these estimates may be affected by factors such as changing market conditions , technological advances in the energy industry or changes in regulations governing that industry . other key inputs that require judgment include discount rates , comparable market transactions , estimated useful lives and probability of future transactions . the most significant assumptions requiring the most judgment involve identifying and estimating the fair value of intangible assets and property , plant and equipment and the associated useful lives for establishing amortization periods . to finalize purchase accounting for significant transactions , nep may utilize the services of independent valuation specialists to assist in the determination of the fair value of acquired intangible assets and property , plant and equipment . the allocation of the purchase price may be modified up to one year from the date of the acquisition if new information is obtained about the fair value of assets acquired and liabilities assumed . there are also significant judgments involved in estimating the value of any contingent purchase consideration , for example , additional cash or stock consideration to be earned based on the future results or performance of the acquired business . the value of this potential additional consideration is required to be estimated and recorded as part of the purchase accounting for the acquisition in the period when the transaction is effective . each quarter these estimates must be reevaluated based on actual results achieved and changes in circumstances , and the contingent consideration adjusted to reflect any change in fair value . see note 6 - contingent consideration . 49 goodwill and other intangible assets goodwill acquired in connection with business combinations represents the excess of consideration over the fair value of net assets acquired . for goodwill and intangible assets with indefinite lives , an assessment for impairment is performed annually or whenever an event indicating impairment may have occurred . nep completes the annual impairment test for goodwill and indefinite-lived intangibles using an assessment date of october 1. goodwill is reviewed for impairment by comparing the carrying value of a reporting unit 's net assets , including allocated goodwill , to the estimated fair value of a reporting unit . nep estimates the fair value of a reporting unit using a combination of the income , market and cost approaches . determining the fair value of a reporting unit requires judgment and the use of significant estimates and assumptions . such estimates and assumptions include revenue growth rates , future operating margins , the weighted average cost of capital , and future market conditions , among others . if a reporting unit 's carrying value is greater than its fair value , a second step is performed whereby the implied fair value of goodwill is estimated by allocating the fair value of a reporting unit in a hypothetical purchase price allocation analysis . a goodwill impairment charge would be recognized for the amount by which the carrying value of goodwill exceeds its reassessed fair value . nep performed its annual goodwill impairment test in october 2018 and determined , based on the results , that no goodwill impairment charge was required . quantitative and qualitative disclosures about market risk nep is exposed to several market risks in its normal business activities . market risk is the potential loss that may result from market changes associated with its business . the types of market risks include interest rate and counterparty credit risks . interest rate risk nep is exposed to risk resulting from changes in interest rates associated with outstanding and expected future debt issuances and borrowings . nep manages interest rate exposure by monitoring current interest rates , entering into interest rate swap contracts and using a combination of fixed rate and variable rate debt . interest rate swaps are used to mitigate and adjust interest rate exposure when deemed appropriate based upon market conditions or when required by financing agreements . nep has long-term debt instruments that subject it to the risk of loss associated with movements in market interest rates . at december 31 , 2018 , approximately 2 % of the long-term debt , including current maturities , was exposed to fluctuations in interest expense as the remaining balance was

liquidity and capital resources nep 's ongoing operations use cash to fund o & m expenses , maintenance capital expenditures , debt service payments and distributions to common and preferred unitholders and holders of noncontrolling interests . nep expects to satisfy these requirements primarily with internally generated cash flow . in addition , as a growth-oriented limited partnership , nep expects from time to time to make acquisitions and other investments . these acquisitions and investments are expected to be funded with borrowings under credit facilities or term loans , issuances of indebtedness , issuances of additional nep common units or preferred units , capital raised pursuant to other financing structures , cash on hand and cash generated from operations . these sources of funds are expected to be adequate to provide for nep 's short-term and long-term liquidity and capital needs , although its ability to make future acquisitions , expand existing projects and increase its distributions to common unitholders will depend on its ability to access the capital markets on acceptable terms . as a normal part of its business , depending on market conditions , nep expects from time to time to consider opportunities to repay , redeem , repurchase or refinance its indebtedness . in addition , nep expects from time to time to consider potential investments in new acquisitions . these events may cause nep to seek additional debt or equity financing , which may not be available on acceptable terms or at all . additional debt financing , if available , could impose operating restrictions , additional cash payment obligations and additional covenants . nep opco has agreed to allow neer or one of its affiliates to withdraw funds received by nep opco or its subsidiaries and to hold those funds in accounts of neer or one of its affiliates to the extent the funds are not required to pay project costs or otherwise required to be maintained by nep 's subsidiaries , until the financing agreements permit distributions to be made , or , in the case of nep opco , until such funds are required to make distributions or to pay expenses or other operating costs .


 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 nep 's ongoing operations use cash to fund o & m expenses , maintenance capital expenditures , debt service payments and distributions to common and preferred unitholders and holders of noncontrolling interests . nep expects to satisfy these requirements primarily with internally generated cash flow . in addition , as a growth-oriented limited partnership , nep expects from time to time to make acquisitions and other investments . these acquisitions and investments are expected to be funded with borrowings under credit facilities or term loans , issuances of indebtedness , issuances of additional nep common units or preferred units , capital raised pursuant to other financing structures , cash on hand and cash generated from operations . these sources of funds are expected to be adequate to provide for nep 's short-term and long-term liquidity and capital needs , although its ability to make future acquisitions , expand existing projects and increase its distributions to common unitholders will depend on its ability to access the capital markets on acceptable terms . as a normal part of its business , depending on market conditions , nep expects from time to time to consider opportunities to repay , redeem , repurchase or refinance its indebtedness . in addition , nep expects from time to time to consider potential investments in new acquisitions . these events may cause nep to seek additional debt or equity financing , which may not be available on acceptable terms or at all . additional debt financing , if available , could impose operating restrictions , additional cash payment obligations and additional covenants . nep opco has agreed to allow neer or one of its affiliates to withdraw funds received by nep opco or its subsidiaries and to hold those funds in accounts of neer or one of its affiliates to the extent the funds are not required to pay project costs or otherwise required to be maintained by nep 's subsidiaries , until the financing agreements permit distributions to be made , or , in the case of nep opco , until such funds are required to make distributions or to pay expenses or other operating costs .
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 Suspicious Activity Report : operating expenses operations and maintenance o & m expenses include interconnection costs , labor expenses , turbine servicing costs , land payments , insurance , materials , supplies , shared services and administrative expenses attributable to nep 's projects , and costs and expenses under the msa , asas and o & m agreements ( see note 13 ) . o & m expenses also include the cost of maintaining and replacing certain parts for the projects in the portfolio to maintain , over the long term , operating income or operating capacity . o & m expenses increased $ 9 million during the year ended december 31 , 2018 primarily due to an increase of approximately $ 12 million in idr fees related to growth in nep 's distributions to its common unitholders and increases in o & m expenses at various projects , partly offset by a decrease of approximately $ 8 million as a result of the sale of canadian holdings . 41 o & m expenses related to the existing portfolio are expected to remain relatively stable from year to year . however , nep 's o & m expenses are likely to increase as nep acquires new projects . depreciation and amortization depreciation and amortization expense reflects costs associated with depreciation and amortization of nep 's assets , based on depreciable asset lives and consistent depreciation methodologies . for certain of the renewable energy projects , citcs have been elected and are recorded as a reduction in property , plant and equipment - net on the consolidated balance sheets and amortized as a reduction to depreciation and amortization expense over the estimated life of the related property . depreciation and amortization expense also includes a provision for wind and solar facility dismantlement , asset removal costs and accretion related to asset retirement obligations and the amortization of finite-lived intangible assets . depreciation and amortization expense decreased $ 23 million during the year ended december 31 , 2018 primarily as a result of the sale of canadian holdings . gain on disposal of canadian holdings during the year ended december 31 , 2018 , a subsidiary of nep completed the sale of canadian holdings and nep recognized a pre-tax gain of approximately $ 153 million . see note 2 - disposal of canadian holdings . other income ( deductions ) interest expense interest expense primarily consists of interest under long-term debt agreements and mark-to-market gains and losses on interest rate contracts . interest expense increased approximately $ 49 million during the year ended december 31 , 2018 primarily due to unfavorable mark-to-market activity of $ 56 million , partly offset by a decrease of $ 13 million in interest expense associated with the sale of canadian holdings . benefits associated with differential membership interests - net for the year ended december 31 , 2017 , benefits associated with differential membership interests - net reflects benefits recognized by nep as third-party investors received their portion of the economic attributes , including income tax attributes , of the underlying wind projects , net of associated costs . nep recognized income related to differential membership interests of approximately $ 370 million for the year ended december 31 , 2018 which , due to the adoption of an accounting standards update , is reflected as a loss attributable to noncontrolling interests in the consolidated statements of income , of which approximately $ 231 million related to the change in federal corporate income tax rates that became effective january 1 , 2018. see note 2 - differential membership interests . approximately $ 240 million of the loss attributable to differential membership interests relates to nee 's noncontrolling interest and $ 130 million is reflected as net income attributable to nep . other - net the increase in other - net for the year ended december 31 , 2018 primarily reflects an approximately $ 17 million increase related to 2018 gains on foreign currency exchange contracts ( see note 7 ) and the difference between the total net identifiable assets at fair value and the total consideration transferred for an acquisition in december 2018 ( see note 3 ) . income taxes for periods through december 31 , 2017 , when nep acquired a neer project , income taxes were calculated on the predecessor method using the separate return method applied to the group of renewable energy projects acquired . as a result of the governance changes discussed in note 3 , beginning in january 1 , 2018 , acquisitions from neer are no longer treated as common control acquisitions , and income taxes are calculated on the successor method under which taxes are calculated for nep as a single taxpaying corporation for u.s. federal and state income taxes ( based on its election to be taxed as a corporation ) . because nep opco is a limited partnership , nep only recognizes in income its applicable ownership share of u.s. income taxes related to the u.s. projects and , prior to the sale of canadian holdings , the canadian projects . nep 's former canadian subsidiaries were all canadian taxpayers , and therefore nep recognized in income all of the canadian taxes . income taxes include nep 's applicable ownership share of u.s. taxes and 100 % of canadian taxes . net income or loss attributable to noncontrolling interests includes no u.s. taxes and neer 's applicable ownership share of canadian taxes . net income attributable to nep includes nep 's applicable ownership share of u.s. and canadian taxes . for the year ended december 31 , 2018 , nep recorded income tax expense of approximately $ 6 million on income before income taxes of $ 273 million , resulting in an effective tax rate of approximately 2 % . story_separator_special_tag no u.s. income taxes were provided with regard to these entities for periods prior to the nep acquisition date . see note 5 . impairment of long-lived assets nep evaluates long-lived assets , including finite-lived intangible assets , for impairment when events or changes in circumstances indicate that the carrying amount may not be recoverable . an impairment loss is required to be recognized if the carrying value of the asset exceeds the undiscounted future net cash flows associated with that asset . the impairment loss to be recognized is the amount by which the carrying value of the long-lived asset exceeds the asset 's fair value . in most instances , the fair value is determined by discounting estimated future cash flows using an appropriate interest rate . the amount of future net cash flows , the timing of such cash flows and the determination of an appropriate interest rate all involve estimates and judgments about future events . in particular , the aggregate amount of cash flows determines whether an impairment exists , and the timing of the cash flows is critical in determining fair value for the purposes of determining the impairment loss to be recognized . because each assessment is based on the facts and circumstances associated with each long-lived asset , the effects of changes in assumptions can not be generalized . see note 15 - pg & e bankruptcy for a discussion of an impairment analysis related to the pg & e bankruptcy filing . business combinations certain assumptions and estimates are employed in determining the fair value of assets acquired , evaluating the fair value of liabilities assumed , as well as in determining the allocation of goodwill to a reporting unit . these estimates may be affected by factors such as changing market conditions , technological advances in the energy industry or changes in regulations governing that industry . other key inputs that require judgment include discount rates , comparable market transactions , estimated useful lives and probability of future transactions . the most significant assumptions requiring the most judgment involve identifying and estimating the fair value of intangible assets and property , plant and equipment and the associated useful lives for establishing amortization periods . to finalize purchase accounting for significant transactions , nep may utilize the services of independent valuation specialists to assist in the determination of the fair value of acquired intangible assets and property , plant and equipment . the allocation of the purchase price may be modified up to one year from the date of the acquisition if new information is obtained about the fair value of assets acquired and liabilities assumed . there are also significant judgments involved in estimating the value of any contingent purchase consideration , for example , additional cash or stock consideration to be earned based on the future results or performance of the acquired business . the value of this potential additional consideration is required to be estimated and recorded as part of the purchase accounting for the acquisition in the period when the transaction is effective . each quarter these estimates must be reevaluated based on actual results achieved and changes in circumstances , and the contingent consideration adjusted to reflect any change in fair value . see note 6 - contingent consideration . 49 goodwill and other intangible assets goodwill acquired in connection with business combinations represents the excess of consideration over the fair value of net assets acquired . for goodwill and intangible assets with indefinite lives , an assessment for impairment is performed annually or whenever an event indicating impairment may have occurred . nep completes the annual impairment test for goodwill and indefinite-lived intangibles using an assessment date of october 1. goodwill is reviewed for impairment by comparing the carrying value of a reporting unit 's net assets , including allocated goodwill , to the estimated fair value of a reporting unit . nep estimates the fair value of a reporting unit using a combination of the income , market and cost approaches . determining the fair value of a reporting unit requires judgment and the use of significant estimates and assumptions . such estimates and assumptions include revenue growth rates , future operating margins , the weighted average cost of capital , and future market conditions , among others . if a reporting unit 's carrying value is greater than its fair value , a second step is performed whereby the implied fair value of goodwill is estimated by allocating the fair value of a reporting unit in a hypothetical purchase price allocation analysis . a goodwill impairment charge would be recognized for the amount by which the carrying value of goodwill exceeds its reassessed fair value . nep performed its annual goodwill impairment test in october 2018 and determined , based on the results , that no goodwill impairment charge was required . quantitative and qualitative disclosures about market risk nep is exposed to several market risks in its normal business activities . market risk is the potential loss that may result from market changes associated with its business . the types of market risks include interest rate and counterparty credit risks . interest rate risk nep is exposed to risk resulting from changes in interest rates associated with outstanding and expected future debt issuances and borrowings . nep manages interest rate exposure by monitoring current interest rates , entering into interest rate swap contracts and using a combination of fixed rate and variable rate debt . interest rate swaps are used to mitigate and adjust interest rate exposure when deemed appropriate based upon market conditions or when required by financing agreements . nep has long-term debt instruments that subject it to the risk of loss associated with movements in market interest rates . at december 31 , 2018 , approximately 2 % of the long-term debt , including current maturities , was exposed to fluctuations in interest expense as the remaining balance was

