EXHIBIT 11 NATIONAL SANITARY SUPPLY COMPANY COMPUTATION OF EARNINGS PER SHARE (a) (UNAUDITED) Three Months Ended (thousands, except per share data) March 31, - ---------------------------------- ------------------------- 1997 1996 ------- ------- Computation of Earnings Per Common and Common Equivalent Share Net Income $ 625 $ 832 ======= ======= Average Number of Shares of Common Stock Outstanding 6,181 6,123 Incremental Effect of Unexercised Stock Options 73 65 ------- ------- Average Number of Shares of Common Stock and Common Stock Equivalents Outstanding 6,254 6,188 ======= ======= Earnings per Common and Common Equivalent Share $ 0.10 $ 0.13 ======= ======= Computation of Earnings Per Common Share Assuming Full Dilution Net Income $ 625 $ 832 ======= ======= Average Number of Shares of Common Stock Outstanding 6,181 6,123 Incremental Effect of Unexercised Stock Options 73 100 ------- ------- Average Number of Shares of Common Stock assuming Full Dilution 6,254 6,223 ======= ======= Earnings Per Common Share Assuming Full Dilution $ 0.10 $ 0.13 ======= ======= (a) This calculation is submitted in accordance with the Securities Exchange Act of 1934. Because the incremental effect of unexercised stock options results in dilution of less than 3%, the per share data presented in the consolidated statement of income excludes the impact of common stock equivalents. E-1 Page 9 of 9