in addition to launching new projects for our future growth , we continue to analyze our asset portfolio to ensure capital discipline in all aspects of our business . as a result , we have decided to discontinue the operation of our ammonia pipeline system later this year due to its low profitability and challenging economic outlook . we are also no longer pursuing our delaware basin crude oil pipeline construction project on a stand-alone basis and are actively evaluating a lower cost solution to meet the needs of our customers . these decisions demonstrate our commitment to manage all aspects of our business in a disciplined manner . growth projects additional energy infrastructure to support our nation 's growing export needs remains an important theme for our industry . we have made significant progress to advance our strategy to grow our marine capabilities along the gulf coast for both crude oil and refined products . our seabrook joint venture initiated its first crude oil export in august 2018 , and we announced plans to further expand this terminal with additional storage and dock capabilities . we believe the export options provided through seabrook increases the attractiveness of our service offering to seamlessly deliver crude oil from the permian basin to the gulf coast waterway to meet our customers ' growing interest in crude exports . the first phase of our newly constructed mvp joint venture marine terminal in pasadena , texas became operational in january 2019 to meet our customers ' increasing desire for refined products storage and export solutions . we continue to make significant progress on the next phase of the terminal at pasadena , with an additional 4 million barrels of storage and additional dock capabilities expected to come online by the end of 2019. discussions with a number of industry participants continue for additional infrastructure needs at this new facility . we remain optimistic about future expansions at pasadena that could double the capacity of this new marine terminal . industry demand for additional pipeline infrastructure continues as well , and construction is underway for a new refined products pipeline segment in central texas that will expand capacity between houston and the dallas-ft. worth metropolitan area . this new pipeline segment is expected to be in-service during mid-2019 . we are also expanding the western leg of our texas refined products pipeline by mid-2020 . our texas refined products pipeline system has been oversubscribed for quite some time , and we are pleased to meet the industry 's need for more capacity through these strategic enhancements to our essential refined products pipeline system . in 2018 , we also announced plans to form a new crude oil pipeline joint venture with energy transfer , mplx and delek to deliver crude oil from the permian basin to our terminal in the houston area and energy transfer 's terminal in nederland , texas . this permian gulf coast ( “ pgc ” ) pipeline is intended to serve the gulf coast refining complex from texas to louisiana as well as multiple crude oil export facilities . while advancing the pgc stand-alone project , we also remain in discussions with other industry players to assess the potential to combine similar projects to capture capital and operating efficiencies that may be available for all parties . recent developments cash distribution . in january 2019 , the board of directors of our general partner declared a quarterly cash distribution of $ 0.9975 per unit for the period of october 1 , 2018 through december 31 , 2018. this quarterly cash distribution was paid on february 14 , 2019 to unitholders of record on february 7 , 2019. the total distribution paid on 228.4 million limited partner units outstanding was $ 227.8 million . 48 debt issuance . in january 2019 , we issued $ 500.0 million of 4.85 % senior notes due 2049 in an underwritten public offering . the notes were issued at 99.371 % of par . net proceeds from this offering were approximately $ 492.5 million after underwriting discounts . the net proceeds from this offering along with cash on hand were used to redeem our 6.55 % senior notes due 2019 , which were paid on february 11 , 2019. ammonia pipeline . in december 2018 , we made the decision to discontinue commercial operations of our ammonia pipeline beginning in late 2019 due to the system 's low profitability and challenging economic outlook . as a result , we have recognized a $ 49.1 million impairment charge . results of operations we believe that investors benefit from having access to the same financial measures utilized by management . operating margin , which is presented in the following tables , is an important measure used by management to evaluate the economic performance of our core operations . operating margin is not a generally accepted accounting principles ( “ gaap ” ) measure , but the components of operating margin are computed using amounts that are determined in accordance with gaap . a reconciliation of operating margin to operating profit , which is its nearest comparable gaap financial measure , is included in the following tables . operating profit includes expense items , such as depreciation , amortization and impairment expense and general and administrative ( “ g & a ” ) expenses , which management does not focus on when evaluating the core profitability of our separate operating segments . additionally , product margin , which management primarily uses to evaluate the profitability of our commodity-related activities , is provided in these tables . product margin is a non-gaap measure ; however , its components of product sales revenue and cost of product sales are determined in accordance with gaap . our butane blending , fractionation and other commodity-related activities generate significant revenue . story_separator_special_tag for purposes of this table , we have reflected no assumed borrowings under our revolving credit facility or commercial paper program for any periods presented . we have included interest obligations based on the stated amounts of our fixed-rate obligations . ( 2 ) we have entered into product storage contracts with third parties . the cost of storage services is recognized in cost of product sales on our consolidated statements of income . ( 3 ) represents the projected benefit obligation of our pension and postretirement medical plans less the fair value of plan assets . ( 4 ) includes product purchase commitments for which the price provisions are indexed based on the date of delivery . we have estimated the value of these commitments using the related index price curve as of december 31 , 2018. also , we have excluded certain product purchase agreements for which there is no specified or minimum quantity . ( 5 ) as of december 31 , 2018 , we had entered into exchange-traded futures contracts representing 4.1 million barrels of petroleum products that we expect to sell in the future and 0.9 million barrels of butane we expect to purchase in the future . at december 31 , 2018 , we had recorded a net asset of $ 55.0 million and held margin deposits of $ 37.3 million . we have excluded from this table the future net cash outflows , if any , under these futures contracts and the amounts of future margin deposit requirements because those amounts are uncertain . ( 6 ) settlements of our ltip awards will differ from these reported amounts primarily due to differences between actual and current estimates of payout percentages and completion of the remaining portion of the requisite service periods . environmental our operations are subject to federal , state and local environmental laws and regulations . we have accrued liabilities for estimated costs at our facilities and properties . we record liabilities when environmental costs are probable and can be reasonably estimated . the determination of amounts recorded for environmental liabilities involves significant judgments and assumptions by management . due to the inherent uncertainties involved in determining environmental liabilities , it is reasonably possible that the actual amounts required to extinguish these liabilities could be materially different from those we have recognized . other items pipeline tariff increase . the federal energy regulatory commission ( “ ferc ” ) regulates the rates charged on interstate common carrier pipeline operations primarily through an indexing methodology , which establishes the maximum amount by which index-based tariffs can be adjusted each year . approximately 40 % of our refined products tariffs are subject to this indexing methodology . the remaining 60 % of our refined products tariffs are either subject to regulations by the states in which we operate or are approved for market-based rates by the ferc , 59 and in both cases these rates can be adjusted at our discretion based on market factors . the current ferc-approved indexing method is the annual change in the producer price index for finished goods ( “ ppi-fg ” ) plus 1.23 % . based on the preliminary estimates for this indexing methodology in 2018 , we expect to increase virtually all of our refined products pipeline rates by approximately 4.3 % on july 1 , 2019. most of the tariffs on our crude oil pipelines are established at negotiated rates that generally provide for annual adjustments in line with changes in the ferc index , subject to certain modifications . we also expect to increase the rates of our crude oil pipelines by approximately 4 % on average in july 2019. sale of interest in bridgetex . in september 2018 , we sold a 20 % interest in bridgetex to an affiliate of omers infrastructure management inc. , which reduced our ongoing ownership in bridgetex to a 30 % interest . we received $ 575.6 million in cash from the sale and recorded a gain of $ 353.8 million on our consolidated statements of income . we continue to serve as the operator of bridgetex . crude oil pipeline contract renewals . due to increased competition , recent contract renewals have resulted in lower average crude oil tariff rates for term commitments . for example , the initial term of our contracts for the longhorn pipeline expired in september 2018 , and some shippers elected to extend their contracts under current terms for an additional two years , while others executed new contracts with lower incentive tariff rates and terms up to 10 years , resulting in an average contract term of five years and a lower average tariff rate . although we continue to believe that demand for capacity on longhorn and our other crude oil pipelines remains strong , the pricing environment for term commitments on crude oil pipelines is very competitive , and we continue to assume the average tariff rates agreed to for term commitments on our crude oil pipelines , including the crude oil pipelines of our joint ventures , will be lower upon future renewals . commodity derivative agreements . certain of the business activities in which we engage result in our owning various commodities , which exposes us to commodity price risk . we use forward physical commodity contracts and exchange-based futures contracts to help manage this commodity price risk . we use forward physical contracts to purchase butane and sell refined products . we account for these forward physical contracts as normal purchase and sale contracts , using traditional accrual accounting . we use futures contracts to hedge against changes in prices of petroleum products that we expect to sell or purchase in future periods . we use and account for those futures contracts that qualify for hedge accounting treatment as either cash flow or fair value hedges , and we use and account for those futures contracts that do not qualify for hedge accounting treatment

liquidity and capital resources cash flows and capital expenditures operating activities . net cash provided by operating activities was $ 973.3 million , $ 1,131.2 million and $ 1,353.0 million for the years ended december 31 , 2016 , 2017 and 2018 , respectively . the $ 221.8 million increase from 2017 to 2018 was due to higher net income as previously described and changes in our working capital , partially offset by adjustments for non-cash items . the $ 157.9 million increase from 2016 to 2017 was due to higher net income as previously described , adjustments to non-cash items and changes in our working capital . investing activities . net cash used by investing activities for the years ended december 31 , 2016 , 2017 and 2018 was $ 866.6 million , $ 593.2 million and $ 119.3 million , respectively . during 2018 , we sold a portion of our interest in bridgetex for cash proceeds of $ 575.6 million . also during 2018 , we spent $ 562.3 million on capital expenditures , which included $ 88.7 million for maintenance capital , $ 425.0 million for our expansion capital projects and $ 48.6 million for undivided joint interest projects for which cash was received from a third party . additionally , we contributed capital of $ 216.4 million in conjunction with our joint venture capital projects , which we account for as investments in non-controlled entities .


 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 cash flows and capital expenditures operating activities . net cash provided by operating activities was $ 973.3 million , $ 1,131.2 million and $ 1,353.0 million for the years ended december 31 , 2016 , 2017 and 2018 , respectively . the $ 221.8 million increase from 2017 to 2018 was due to higher net income as previously described and changes in our working capital , partially offset by adjustments for non-cash items . the $ 157.9 million increase from 2016 to 2017 was due to higher net income as previously described , adjustments to non-cash items and changes in our working capital . investing activities . net cash used by investing activities for the years ended december 31 , 2016 , 2017 and 2018 was $ 866.6 million , $ 593.2 million and $ 119.3 million , respectively . during 2018 , we sold a portion of our interest in bridgetex for cash proceeds of $ 575.6 million . also during 2018 , we spent $ 562.3 million on capital expenditures , which included $ 88.7 million for maintenance capital , $ 425.0 million for our expansion capital projects and $ 48.6 million for undivided joint interest projects for which cash was received from a third party . additionally , we contributed capital of $ 216.4 million in conjunction with our joint venture capital projects , which we account for as investments in non-controlled entities .
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 Suspicious Activity Report : in addition to launching new projects for our future growth , we continue to analyze our asset portfolio to ensure capital discipline in all aspects of our business . as a result , we have decided to discontinue the operation of our ammonia pipeline system later this year due to its low profitability and challenging economic outlook . we are also no longer pursuing our delaware basin crude oil pipeline construction project on a stand-alone basis and are actively evaluating a lower cost solution to meet the needs of our customers . these decisions demonstrate our commitment to manage all aspects of our business in a disciplined manner . growth projects additional energy infrastructure to support our nation 's growing export needs remains an important theme for our industry . we have made significant progress to advance our strategy to grow our marine capabilities along the gulf coast for both crude oil and refined products . our seabrook joint venture initiated its first crude oil export in august 2018 , and we announced plans to further expand this terminal with additional storage and dock capabilities . we believe the export options provided through seabrook increases the attractiveness of our service offering to seamlessly deliver crude oil from the permian basin to the gulf coast waterway to meet our customers ' growing interest in crude exports . the first phase of our newly constructed mvp joint venture marine terminal in pasadena , texas became operational in january 2019 to meet our customers ' increasing desire for refined products storage and export solutions . we continue to make significant progress on the next phase of the terminal at pasadena , with an additional 4 million barrels of storage and additional dock capabilities expected to come online by the end of 2019. discussions with a number of industry participants continue for additional infrastructure needs at this new facility . we remain optimistic about future expansions at pasadena that could double the capacity of this new marine terminal . industry demand for additional pipeline infrastructure continues as well , and construction is underway for a new refined products pipeline segment in central texas that will expand capacity between houston and the dallas-ft. worth metropolitan area . this new pipeline segment is expected to be in-service during mid-2019 . we are also expanding the western leg of our texas refined products pipeline by mid-2020 . our texas refined products pipeline system has been oversubscribed for quite some time , and we are pleased to meet the industry 's need for more capacity through these strategic enhancements to our essential refined products pipeline system . in 2018 , we also announced plans to form a new crude oil pipeline joint venture with energy transfer , mplx and delek to deliver crude oil from the permian basin to our terminal in the houston area and energy transfer 's terminal in nederland , texas . this permian gulf coast ( “ pgc ” ) pipeline is intended to serve the gulf coast refining complex from texas to louisiana as well as multiple crude oil export facilities . while advancing the pgc stand-alone project , we also remain in discussions with other industry players to assess the potential to combine similar projects to capture capital and operating efficiencies that may be available for all parties . recent developments cash distribution . in january 2019 , the board of directors of our general partner declared a quarterly cash distribution of $ 0.9975 per unit for the period of october 1 , 2018 through december 31 , 2018. this quarterly cash distribution was paid on february 14 , 2019 to unitholders of record on february 7 , 2019. the total distribution paid on 228.4 million limited partner units outstanding was $ 227.8 million . 48 debt issuance . in january 2019 , we issued $ 500.0 million of 4.85 % senior notes due 2049 in an underwritten public offering . the notes were issued at 99.371 % of par . net proceeds from this offering were approximately $ 492.5 million after underwriting discounts . the net proceeds from this offering along with cash on hand were used to redeem our 6.55 % senior notes due 2019 , which were paid on february 11 , 2019. ammonia pipeline . in december 2018 , we made the decision to discontinue commercial operations of our ammonia pipeline beginning in late 2019 due to the system 's low profitability and challenging economic outlook . as a result , we have recognized a $ 49.1 million impairment charge . results of operations we believe that investors benefit from having access to the same financial measures utilized by management . operating margin , which is presented in the following tables , is an important measure used by management to evaluate the economic performance of our core operations . operating margin is not a generally accepted accounting principles ( “ gaap ” ) measure , but the components of operating margin are computed using amounts that are determined in accordance with gaap . a reconciliation of operating margin to operating profit , which is its nearest comparable gaap financial measure , is included in the following tables . operating profit includes expense items , such as depreciation , amortization and impairment expense and general and administrative ( “ g & a ” ) expenses , which management does not focus on when evaluating the core profitability of our separate operating segments . additionally , product margin , which management primarily uses to evaluate the profitability of our commodity-related activities , is provided in these tables . product margin is a non-gaap measure ; however , its components of product sales revenue and cost of product sales are determined in accordance with gaap . our butane blending , fractionation and other commodity-related activities generate significant revenue . story_separator_special_tag for purposes of this table , we have reflected no assumed borrowings under our revolving credit facility or commercial paper program for any periods presented . we have included interest obligations based on the stated amounts of our fixed-rate obligations . ( 2 ) we have entered into product storage contracts with third parties . the cost of storage services is recognized in cost of product sales on our consolidated statements of income . ( 3 ) represents the projected benefit obligation of our pension and postretirement medical plans less the fair value of plan assets . ( 4 ) includes product purchase commitments for which the price provisions are indexed based on the date of delivery . we have estimated the value of these commitments using the related index price curve as of december 31 , 2018. also , we have excluded certain product purchase agreements for which there is no specified or minimum quantity . ( 5 ) as of december 31 , 2018 , we had entered into exchange-traded futures contracts representing 4.1 million barrels of petroleum products that we expect to sell in the future and 0.9 million barrels of butane we expect to purchase in the future . at december 31 , 2018 , we had recorded a net asset of $ 55.0 million and held margin deposits of $ 37.3 million . we have excluded from this table the future net cash outflows , if any , under these futures contracts and the amounts of future margin deposit requirements because those amounts are uncertain . ( 6 ) settlements of our ltip awards will differ from these reported amounts primarily due to differences between actual and current estimates of payout percentages and completion of the remaining portion of the requisite service periods . environmental our operations are subject to federal , state and local environmental laws and regulations . we have accrued liabilities for estimated costs at our facilities and properties . we record liabilities when environmental costs are probable and can be reasonably estimated . the determination of amounts recorded for environmental liabilities involves significant judgments and assumptions by management . due to the inherent uncertainties involved in determining environmental liabilities , it is reasonably possible that the actual amounts required to extinguish these liabilities could be materially different from those we have recognized . other items pipeline tariff increase . the federal energy regulatory commission ( “ ferc ” ) regulates the rates charged on interstate common carrier pipeline operations primarily through an indexing methodology , which establishes the maximum amount by which index-based tariffs can be adjusted each year . approximately 40 % of our refined products tariffs are subject to this indexing methodology . the remaining 60 % of our refined products tariffs are either subject to regulations by the states in which we operate or are approved for market-based rates by the ferc , 59 and in both cases these rates can be adjusted at our discretion based on market factors . the current ferc-approved indexing method is the annual change in the producer price index for finished goods ( “ ppi-fg ” ) plus 1.23 % . based on the preliminary estimates for this indexing methodology in 2018 , we expect to increase virtually all of our refined products pipeline rates by approximately 4.3 % on july 1 , 2019. most of the tariffs on our crude oil pipelines are established at negotiated rates that generally provide for annual adjustments in line with changes in the ferc index , subject to certain modifications . we also expect to increase the rates of our crude oil pipelines by approximately 4 % on average in july 2019. sale of interest in bridgetex . in september 2018 , we sold a 20 % interest in bridgetex to an affiliate of omers infrastructure management inc. , which reduced our ongoing ownership in bridgetex to a 30 % interest . we received $ 575.6 million in cash from the sale and recorded a gain of $ 353.8 million on our consolidated statements of income . we continue to serve as the operator of bridgetex . crude oil pipeline contract renewals . due to increased competition , recent contract renewals have resulted in lower average crude oil tariff rates for term commitments . for example , the initial term of our contracts for the longhorn pipeline expired in september 2018 , and some shippers elected to extend their contracts under current terms for an additional two years , while others executed new contracts with lower incentive tariff rates and terms up to 10 years , resulting in an average contract term of five years and a lower average tariff rate . although we continue to believe that demand for capacity on longhorn and our other crude oil pipelines remains strong , the pricing environment for term commitments on crude oil pipelines is very competitive , and we continue to assume the average tariff rates agreed to for term commitments on our crude oil pipelines , including the crude oil pipelines of our joint ventures , will be lower upon future renewals . commodity derivative agreements . certain of the business activities in which we engage result in our owning various commodities , which exposes us to commodity price risk . we use forward physical commodity contracts and exchange-based futures contracts to help manage this commodity price risk . we use forward physical contracts to purchase butane and sell refined products . we account for these forward physical contracts as normal purchase and sale contracts , using traditional accrual accounting . we use futures contracts to hedge against changes in prices of petroleum products that we expect to sell or purchase in future periods . we use and account for those futures contracts that qualify for hedge accounting treatment as either cash flow or fair value hedges , and we use and account for those futures contracts that do not qualify for hedge accounting treatment

