llc 201d ) , that will focus on the deployment of a nationwide 4g wire- less network . we , together with the other members of the investor group , have invested $ 3.2 billion in clearwire llc . our portion of the investment was $ 1.05 billion . as a result of our investment , we received ownership units ( 201cownership units 201d ) of clearwire llc and class b stock ( 201cvoting stock 201d ) of clearwire corporation , the pub- licly traded holding company that controls clearwire llc . the voting stock has voting rights equal to those of the publicly traded class a stock of clearwire corporation , but has only minimal economic rights . we hold our economic rights through the owner- ship units , which have limited voting rights . one ownership unit combined with one share of voting stock are exchangeable into one share of clearwire corporation 2019s publicly traded class a stock . at closing , we received 52.5 million ownership units and 52.5 million shares of voting stock , which represents an approx- imate 7% ( 7 % ) ownership interest on a fully diluted basis . during the first quarter of 2009 , the purchase price per share is expected to be adjusted based on the trading prices of clearwire corporation 2019s publicly traded class a stock . after the post-closing adjustment , we anticipate that we will have an approximate 8% ( 8 % ) ownership interest on a fully diluted basis . in connection with the clearwire transaction , we entered into an agreement with sprint that allows us to offer wireless services utilizing certain of sprint 2019s existing wireless networks and an agreement with clearwire llc that allows us to offer wireless serv- ices utilizing clearwire 2019s next generation wireless broadband network . we allocated a portion of our $ 1.05 billion investment to the related agreements . we will account for our investment under the equity method and record our share of net income or loss one quarter in arrears . clearwire llc is expected to incur losses in the early years of operation , which under the equity method of accounting , will be reflected in our future operating results and reduce the cost basis of our investment . we evaluated our investment at december 31 , 2008 to determine if an other than temporary decline in fair value below our cost basis had occurred . the primary input in estimating the fair value of our investment was the quoted market value of clearwire publicly traded class a shares at december 31 , 2008 , which declined significantly from the date of our initial agreement in may 2008 . as a result of the severe decline in the quoted market value , we recognized an impairment in other income ( expense ) of $ 600 million to adjust our cost basis in our investment to its esti- mated fair value . in the future , our evaluation of other than temporary declines in fair value of our investment will include a comparison of actual operating results and updated forecasts to the projected discounted cash flows that were used in making our initial investment decision , other impairment indicators , such as changes in competition or technology , as well as a comparison to the value that would be obtained by exchanging our investment into clearwire corporation 2019s publicly traded class a shares . cost method airtouch communications , inc . we hold two series of preferred stock of airtouch communica- tions , inc . ( 201cairtouch 201d ) , a subsidiary of vodafone , which are redeemable in april 2020 . as of december 31 , 2008 and 2007 , the airtouch preferred stock was recorded at $ 1.479 billion and $ 1.465 billion , respectively . as of december 31 , 2008 , the estimated fair value of the airtouch preferred stock was $ 1.357 billion , which is below our carrying amount . the recent decline in fair value is attributable to changes in interest rates . we have determined this decline to be temporary . the factors considered were the length of time and the extent to which the market value has been less than cost , the credit rating of airtouch , and our intent and ability to retain the investment for a period of time sufficient to allow for recovery . specifically , we expect to hold the two series of airtouch preferred stock until their redemption in 2020 . the dividend and redemption activity of the airtouch preferred stock determines the dividend and redemption payments asso- ciated with substantially all of the preferred shares issued by one of our consolidated subsidiaries , which is a vie . the subsidiary has three series of preferred stock outstanding with an aggregate redemption value of $ 1.750 billion . substantially all of the preferred shares are redeemable in april 2020 at a redemption value of $ 1.650 billion . as of december 31 , 2008 and 2007 , the two redeemable series of subsidiary preferred shares were recorded at $ 1.468 billion and $ 1.465 billion , respectively , and those amounts are included in other noncurrent liabilities . the one nonredeemable series of subsidiary preferred shares was recorded at $ 100 million as of both december 31 , 2008 and 2007 and those amounts are included in minority interest on our consolidated balance sheet . investment income ( loss ) , net .

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year ended december 31 ( in millions ) | 2008 | 2007 | 2006
gains on sales and exchanges of investments net | $ 8 | $ 151 | $ 733
investment impairment losses | -28 ( 28 ) | -4 ( 4 ) | -4 ( 4 )
unrealized gains ( losses ) on trading securities and hedged items | -1117 ( 1117 ) | 315 | 339
mark to market adjustments on derivatives related to trading securities and hedged items | 1120 | -188 ( 188 ) | -238 ( 238 )
mark to market adjustments on derivatives | 57 | 160 | -18 ( 18 )
interest and dividend income | 149 | 199 | 212
other | -100 ( 100 ) | -32 ( 32 ) | -34 ( 34 )
investment income ( loss ) net | $ 89 | $ 601 | $ 990
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55 comcast 2008 annual report on form 10-k .

Question: what was the percentage change in investment income ( loss ) net from 2007 to 2008?
Program: subtract(89, 601)
Answer: -512.0