{"pre_text": ["marathon oil corporation notes to consolidated financial statements ( g ) this obligation relates to a lease of equipment at united states steel 2019s clairton works cokemaking facility in pennsylvania .", "we are the primary obligor under this lease .", "under the financial matters agreement , united states steel has assumed responsibility for all obligations under this lease .", "this lease is an amortizing financing with a final maturity of 2012 .", "( h ) these notes are senior secured notes of marathon oil canada corporation .", "the notes are secured by substantially all of marathon oil canada corporation 2019s assets .", "in january 2008 , we provided a full and unconditional guarantee covering the payment of all principal and interest due under the senior notes .", "( i ) these obligations as of december 31 , 2009 include $ 36 million related to assets under construction at that date for which a capital lease will commence upon completion of construction .", "the amounts currently reported are based upon the percent of construction completed as of december 31 , 2009 and therefore do not reflect future minimum lease obligations of $ 164 million related to the asset .", "( j ) payments of long-term debt for the years 2010 - 2014 are $ 102 million , $ 246 million , $ 1492 million , $ 287 million and $ 802 million .", "united steel is due to pay $ 17 million in 2010 , $ 161 million in 2011 , $ 19 million in 2012 , and $ 11 for year 2014 .", "( k ) in the event of a change in control , as defined in the related agreements , debt obligations totaling $ 662 million at december 31 , 2009 , may be declared immediately due and payable .", "( l ) see note 16 for information on interest rate swaps .", "20 .", "asset retirement obligations the following summarizes the changes in asset retirement obligations : ( in millions ) 2009 2008 ."], "post_text": ["asset retirement obligations as of december 31 ( a ) $ 1102 $ 965 ( a ) includes asset retirement obligation of $ 3 and $ 2 million classified as short-term at december 31 , 2009 , and 2008. ."], "table": [["( in millions )", "2009", "2008"], ["asset retirement obligations as of january 1", "$ 965", "$ 1134"], ["liabilities incurred including acquisitions", "14", "30"], ["liabilities settled", "-65 ( 65 )", "-94 ( 94 )"], ["accretion expense ( included in depreciation depletion and amortization )", "64", "66"], ["revisions to previous estimates", "124", "24"], ["held for sale", "-", "-195 ( 195 )"], ["asset retirement obligations as of december 31 ( a )", "$ 1102", "$ 965"]], "table_ori": [["<i>(In millions)</i>", "2009", "2008"], ["Asset retirement obligations as of January 1", "$965", "$1,134"], ["Liabilities incurred, including acquisitions", "14", "30"], ["Liabilities settled", "(65)", "(94)"], ["Accretion expense (included in depreciation, depletion and amortization)", "64", "66"], ["Revisions to previous estimates", "124", "24"], ["Held for sale", "-", "(195)"], ["Asset retirement obligations as of December 31<sup>(a)</sup>", "$1,102", "$965"]]}

Question: by what percentage did asset retirement obligations decrease from 2007 to 2008?
Evidence:
table_7: ( in millions ) the asset retirement obligations as of december 31 ( a ) of 2009 is $ 1102 ; the asset retirement obligations as of december 31 ( a ) of 2008 is $ 965 ;
table_1: ( in millions ) the asset retirement obligations as of january 1 of 2009 is $ 965 ; the asset retirement obligations as of january 1 of 2008 is $ 1134 ;
Program: subtract(965, 1134), divide(#0, 1134)
Answer:
str_answer: -14.9%
exe_answer: -0.14903