stockholders 2019 equity derivative instruments activity , net of tax , included in non-owner changes to equity within the consolidated statements of stockholders 2019 equity for the years ended december 31 , 2008 , 2007 and 2006 is as follows: .
what was the percent change in balance of stockholder equity from the beginning to the end of 2006?
net investment in foreign operations hedge at december 31 , 2008 and 2007 , the company did not have any hedges of foreign currency exposure of net investments in foreign operations . investments hedge during the first quarter of 2006 , the company entered into a zero-cost collar derivative ( the 201csprint nextel derivative 201d ) to protect itself economically against price fluctuations in its 37.6 million shares of sprint nextel corporation ( 201csprint nextel 201d ) non-voting common stock . during the second quarter of 2006 , as a result of sprint nextel 2019s spin-off of embarq corporation through a dividend to sprint nextel shareholders , the company received approximately 1.9 million shares of embarq corporation . the floor and ceiling prices of the sprint nextel derivative were adjusted accordingly . the sprint nextel derivative was not designated as a hedge under the provisions of sfas no . 133 , 201caccounting for derivative instruments and hedging activities . 201d accordingly , to reflect the change in fair value of the sprint nextel derivative , the company recorded a net gain of $ 99 million for the year ended december 31 , 2006 , included in other income ( expense ) in the company 2019s consolidated statements of operations . in december 2006 , the sprint nextel derivative was terminated and settled in cash and the 37.6 million shares of sprint nextel were converted to common shares and sold . the company received aggregate cash proceeds of approximately $ 820 million from the settlement of the sprint nextel derivative and the subsequent sale of the 37.6 million sprint nextel shares . the company recognized a loss of $ 126 million in connection with the sale of the remaining shares of sprint nextel common stock . as described above , the company recorded a net gain of $ 99 million in connection with the sprint nextel derivative . fair value of financial instruments the company 2019s financial instruments include cash equivalents , sigma fund investments , short-term investments , accounts receivable , long-term receivables , accounts payable , accrued liabilities , derivatives and other financing commitments . the company 2019s sigma fund , available-for-sale investment portfolios and derivatives are recorded in the company 2019s consolidated balance sheets at fair value . all other financial instruments , with the exception of long-term debt , are carried at cost , which is not materially different than the instruments 2019 fair values . using quoted market prices and market interest rates , the company determined that the fair value of long- term debt at december 31 , 2008 was $ 2.8 billion , compared to a carrying value of $ 4.1 billion . since considerable judgment is required in interpreting market information , the fair value of the long-term debt is not necessarily indicative of the amount which could be realized in a current market exchange . equity price market risk at december 31 , 2008 , the company 2019s available-for-sale equity securities portfolio had an approximate fair market value of $ 128 million , which represented a cost basis of $ 125 million and a net unrealized loss of $ 3 million . these equity securities are held for purposes other than trading . %%transmsg*** transmitting job : c49054 pcn : 105000000 ***%%pcmsg|102 |00022|yes|no|02/23/2009 19:17|0|0|page is valid , no graphics -- color : n| .