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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)