{"pre_text": ["item 7 .", "management 2019s discussion and analysis of financial condition and results of operations we are a global integrated energy company with significant operations in the north america , africa and europe .", "our operations are organized into four reportable segments : 2022 exploration and production ( 201ce&p 201d ) which explores for , produces and markets liquid hydrocarbons and natural gas on a worldwide basis .", "2022 oil sands mining ( 201cosm 201d ) which mines , extracts and transports bitumen from oil sands deposits in alberta , canada , and upgrades the bitumen to produce and market synthetic crude oil and vacuum gas 2022 integrated gas ( 201cig 201d ) which markets and transports products manufactured from natural gas , such as liquefied natural gas ( 201clng 201d ) and methanol , on a worldwide basis .", "2022 refining , marketing & transportation ( 201crm&t 201d ) which refines , markets and transports crude oil and petroleum products , primarily in the midwest , upper great plains , gulf coast and southeastern regions of the united states .", "certain sections of management 2019s discussion and analysis of financial condition and results of operations include forward-looking statements concerning trends or events potentially affecting our business .", "these statements typically contain words such as 201canticipates , 201d 201cbelieves , 201d 201cestimates , 201d 201cexpects , 201d 201ctargets , 201d 201cplans , 201d 201cprojects , 201d 201ccould , 201d 201cmay , 201d 201cshould , 201d 201cwould 201d or similar words indicating that future outcomes are uncertain .", "in accordance with 201csafe harbor 201d provisions of the private securities litigation reform act of 1995 , these statements are accompanied by cautionary language identifying important factors , though not necessarily all such factors , which could cause future outcomes to differ materially from those set forth in the forward-looking statements .", "we hold a 60 percent interest in equatorial guinea lng holdings limited ( 201cegholdings 201d ) .", "as discussed in note 4 to the consolidated financial statements , effective may 1 , 2007 , we ceased consolidating egholdings .", "our investment is accounted for using the equity method of accounting .", "unless specifically noted , amounts presented for the integrated gas segment for periods prior to may 1 , 2007 , include amounts related to the minority interests .", "management 2019s discussion and analysis of financial condition and results of operations should be read in conjunction with the information under item 1 .", "business , item 1a .", "risk factors , item 6 .", "selected financial data and item 8 .", "financial statements and supplementary data .", "overview exploration and production prevailing prices for the various grades of crude oil and natural gas that we produce significantly impact our revenues and cash flows .", "prices were volatile in 2009 , but not as much as in the previous year .", "prices in 2009 were also lower than in recent years as illustrated by the annual averages for key benchmark prices below. ."], "post_text": ["henry hub natural gas ( dollars per mcf ) ( a ) $ 3.99 $ 9.04 $ 6.86 ( a ) first-of-month price index .", "crude oil prices rose sharply through the first half of 2008 as a result of strong global demand , a declining dollar , ongoing concerns about supplies of crude oil , and geopolitical risk .", "later in 2008 , crude oil prices sharply declined as the u.s .", "dollar rebounded and global demand decreased as a result of economic recession .", "the price decrease continued into 2009 , but reversed after dropping below $ 33.98 in february , ending the year at $ 79.36 .", "our domestic crude oil production is about 62 percent sour , which means that it contains more sulfur than light sweet wti does .", "sour crude oil also tends to be heavier than light sweet crude oil and sells at a discount to light sweet crude oil because of higher refining costs and lower refined product values .", "our international crude oil production is relatively sweet and is generally sold in relation to the dated brent crude benchmark .", "the differential between wti and dated brent average prices narrowed to $ 0.42 in 2009 compared to $ 2.49 in 2008 and $ 0.02 in 2007. ."], "table": [["benchmark", "2009", "2008", "2007"], ["wti crude oil ( dollars per barrel )", "$ 62.09", "$ 99.75", "$ 72.41"], ["dated brent crude oil ( dollars per barrel )", "$ 61.67", "$ 97.26", "$ 72.39"], ["henry hub natural gas ( dollars per mcf ) ( a )", "$ 3.99", "$ 9.04", "$ 6.86"]], "table_ori": [["Benchmark", "2009", "2008", "2007"], ["WTI crude oil (Dollars per barrel)", "$62.09", "$99.75", "$72.41"], ["Dated Brent crude oil (Dollars per barrel)", "$61.67", "$97.26", "$72.39"], ["Henry Hub natural gas (Dollars per mcf)<sup>(a)</sup>", "$3.99", "$9.04", "$6.86"]]}

Question: by what percentage did the average henry hub natural gas benchmark decrease from 2007 to 2009?
Evidence:
table_3: benchmark the henry hub natural gas ( dollars per mcf ) ( a ) of 2009 is $ 3.99 ; the henry hub natural gas ( dollars per mcf ) ( a ) of 2008 is $ 9.04 ; the henry hub natural gas ( dollars per mcf ) ( a ) of 2007 is $ 6.86 ;
Program: subtract(3.99, 6.86), divide(#0, 6.86)
Answer:
str_answer: -41.8%
exe_answer: -0.41837