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Exhibit 12.1

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

 
  Year Ended
December 31,
2014
  Year Ended
December 31,
2013
  Year Ended
December 31,
2012
  Year Ended
December 31,
2011
  Year Ended
December 31,
2010
 

Earnings:

                               

Net increase in net assets resulting from operations

  $ 100,748   $ 96,855   $ 104,444   $ 64,106   $ 39,970  

Income tax expense (benefit) and excise taxes

    6,287     (35 )   10,820     6,288     941  

Total earnings before taxes

  $ 107,035   $ 96,820   $ 115,264   $ 70,394   $ 40,911  

Fixed Charges:

                               

Interest expense

  $ 23,589   $ 20,238   $ 15,631   $ 13,518   $ 9,058  

Total fixed charges

  $ 23,589   $ 20,238   $ 15,631   $ 13,518   $ 9,058  

Earnings available to cover fixed charges

  $ 130,624   $ 117,058   $ 130,895   $ 83,912   $ 49,969  

Ratio of earnings to fixed charges

    5.54     5.78     8.37     6.21     5.52  



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