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Exhibit 99.1

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

 
  Three Months
Ended
March 31,
2013
  Year Ended
December 31,
2012
  Year Ended
December 31,
2011
  Year Ended
December 31,
2010
  Year Ended
December 31,
2009
  Year Ended
December 31,
2008
 

Earnings:

                                     

Net increase in net assets resulting from operations

  $ 23,629   $ 104,444   $ 64,106   $ 39,970   $ 11,956   $ 10,934  

Income tax expense (benefit) and excise taxes

    2,051     10,820     6,288     941     (2,290 )   (3,182 )
                           

Total earnings before taxes

  $ 25,680   $ 115,264   $ 70,394   $ 40,911   $ 9,666   $ 7,752  
                           

Fixed Charges:

                                     

Interest expense

  $ 3,882   $ 15,631   $ 13,518   $ 9,058   $ 3,791   $ 3,778  
                           

Total fixed charges

  $ 3,882   $ 15,631   $ 13,518   $ 9,058   $ 3,791   $ 3,778  
                           

Earnings available to cover fixed charges

  $ 29,562   $ 130,895   $ 83,912   $ 49,969   $ 13,457   $ 11,529  

Ratio of earnings to fixed charges

    7.62     8.37     6.21     5.52     3.55     3.05  



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