(a)  Includes impact of translation of foreign currencies. S-1  Description  Balance at  Beginning  of Period  Additions  Charged to  Costs,  Provisions  and  Expenses  (b)  Deductions  (a)  Balance at  End of  Period  Year ended December 31, 2013 Valuation and qualifying accounts deducted from  assets to which they apply:  Allowance for doubtful accounts.............................. $  3,837 586  (2,708)  1,715 Year ended December 31, 2012 Valuation and qualifying accounts deducted from  assets to which they apply:  Allowance for doubtful accounts.............................. $  3,009 $  1,011  (183)  3,837 Year ended December 31, 2011 Valuation and qualifying accounts deducted from  assets to which they apply:  Allowance for doubtful accounts.............................. $  2,440  $  877  $  (308)  $  3,009 MINERALS TECHNOLOGIES INC. & SUBSIDIARY COMPANIES  SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS  (thousands of dollars) 