marathon oil corporation notes to consolidated financial statements been reported as discontinued operations in the consolidated statements of income and the consolidated statements of cash flows for all periods presented . discontinued operations 2014revenues and pretax income associated with our discontinued irish and gabonese operations are shown in the following table : ( in millions ) 2009 2008 2007 .
by how much did pretax income from discontinued operations decrease from 2007 to 2009?
angola disposition 2013 in july 2009 , we entered into an agreement to sell an undivided 20 percent outside- operated interest in the production sharing contract and joint operating agreement in block 32 offshore angola for $ 1.3 billion , excluding any purchase price adjustments at closing , with an effective date of january 1 , 2009 . the sale closed and we received net proceeds of $ 1.3 billion in february 2010 . the pretax gain on the sale will be approximately $ 800 million . we retained a 10 percent outside-operated interest in block 32 . gabon disposition 2013 in december 2009 , we closed the sale of our operated fields offshore gabon , receiving net proceeds of $ 269 million , after closing adjustments . a $ 232 million pretax gain on this disposition was reported in discontinued operations for 2009 . permian basin disposition 2013 in june 2009 , we closed the sale of our operated and a portion of our outside- operated permian basin producing assets in new mexico and west texas for net proceeds after closing adjustments of $ 293 million . a $ 196 million pretax gain on the sale was recorded . ireland dispositions 2013 in april 2009 , we closed the sale of our operated properties in ireland for net proceeds of $ 84 million , after adjusting for cash held by the sold subsidiary . a $ 158 million pretax gain on the sale was recorded . as a result of this sale , we terminated our pension plan in ireland , incurring a charge of $ 18 million . in june 2009 , we entered into an agreement to sell the subsidiary holding our 19 percent outside-operated interest in the corrib natural gas development offshore ireland . total proceeds were estimated to range between $ 235 million and $ 400 million , subject to the timing of first commercial gas at corrib and closing adjustments . at closing on july 30 , 2009 , the initial $ 100 million payment plus closing adjustments was received . the fair value of the proceeds was estimated to be $ 311 million . fair value of anticipated sale proceeds includes ( i ) $ 100 million received at closing , ( ii ) $ 135 million minimum amount due at the earlier of first gas or december 31 , 2012 , and ( iii ) a range of zero to $ 165 million of contingent proceeds subject to the timing of first commercial gas . a $ 154 million impairment of the held for sale asset was recognized in discontinued operations in the second quarter of 2009 ( see note 16 ) since the fair value of the disposal group was less than the net book value . final proceeds will range between $ 135 million ( minimum amount ) to $ 300 million and are due on the earlier of first commercial gas or december 31 , 2012 . the fair value of the expected final proceeds was recorded as an asset at closing . as a result of new public information in the fourth quarter of 2009 , a writeoff was recorded on the contingent portion of the proceeds ( see note 10 ) . existing guarantees of our subsidiaries 2019 performance issued to irish government entities will remain in place after the sales until the purchasers issue similar guarantees to replace them . the guarantees , related to asset retirement obligations and natural gas production levels , have been indemnified by the purchasers . the fair value of these guarantees is not significant . norwegian disposition 2013 on october 31 , 2008 , we closed the sale of our norwegian outside-operated e&p properties and undeveloped offshore acreage in the heimdal area of the norwegian north sea for net proceeds of $ 301 million , with a pretax gain of $ 254 million as of december 31 , 2008 . pilot travel centers disposition 2013 on october 8 , 2008 , we completed the sale of our 50 percent ownership interest in ptc . sale proceeds were $ 625 million , with a pretax gain on the sale of $ 126 million . immediately preceding the sale , we received a $ 75 million partial redemption of our ownership interest from ptc that was accounted for as a return of investment . this was an investment of our rm&t segment. .