what was the percentual return for s&p 500 in the first year?
performance graph the following graph compares the cumulative five-year total return provided shareholders on our class a common stock relative to the cumulative total returns of the s&p 500 index and two customized peer groups . the old peer group includes intercontinentalexchange , inc. , nyse euronext and the nasdaq omx group inc . the new peer group is the same as the old peer group with the addition of cboe holdings , inc . which completed its initial public offering in june 2010 . an investment of $ 100 ( with reinvestment of all dividends ) is assumed to have been made in our class a common stock , in the peer groups and the s&p 500 index on december 31 , 2005 and its relative performance is tracked through december 31 , 2010 . comparison of 5 year cumulative total return* among cme group inc. , the s&p 500 index , an old peer group and a new peer group 12/05 12/06 12/07 12/08 12/09 12/10 cme group inc . s&p 500 old peer group *$ 100 invested on 12/31/05 in stock or index , including reinvestment of dividends . fiscal year ending december 31 . copyright a9 2011 s&p , a division of the mcgraw-hill companies inc . all rights reserved . new peer group the stock price performance included in this graph is not necessarily indicative of future stock price performance .

|  | 2006 | 2007 | 2008 | 2009 | 2010 |
| :--- | :--- | :--- | :--- | :--- | :--- |
| CME Group Inc. | $139.48 | $188.81 | $58.66 | $96.37 | $93.73 |
| S&P 500 | 115.80 | 122.16 | 76.96 | 97.33 | 111.99 |
| Old Peer Group | 155.58 | 190.78 | 72.25 | 76.11 | 87.61 |
| New Peer Group | 155.58 | 190.78 | 72.25 | 76.11 | 87.61 |

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s_p_500_2010 = 115.80
s_p_500_2005 = 100
return_2010 = s_p_500_2010 - s_p_500_2005
answer = return_2010