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Exhibit 99.1

Main Street Capital Corporation
Computation of Ratio of Earnings to Fixed Charges
(numbers in thousands)

 
  Six Months
Ended
June 30,
2012
  Year Ended
December 31,
2011
  Year Ended
December 31,
2010
  Year Ended
December 31,
2009
  Year Ended
December 31,
2008
  Year Ended
December 31,
2007
 

Earnings:

                                     

Net increase in net assets resulting from operations

  $ 47,992   $ 64,106   $ 39,970   $ 11,956   $ 10,934   $ 2,545  

Income tax expense (benefit) and excise taxes

    2,872     6,288     941     (2,290 )   (3,182 )   3,263  
                           

Total earnings before taxes

  $ 50,864   $ 70,394   $ 40,911   $ 9,666   $ 7,752   $ 5,807  
                           

Fixed Charges:

                                     

Interest expense

  $ 8,044   $ 13,518   $ 9,058   $ 3,791   $ 3,778   $ 3,246  
                           

Total fixed charges

  $ 8,044   $ 13,518   $ 9,058   $ 3,791   $ 3,778   $ 3,246  
                           

Earnings available to cover fixed charges

  $ 58,908   $ 83,912   $ 49,969   $ 13,457   $ 11,529   $ 9,053  

Ratio of earnings to fixed charges

    7.32     6.21     5.52     3.55     3.05     2.79  



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Main Street Capital Corporation Computation of Ratio of Earnings to Fixed Charges (numbers in thousands)