Exhibit 11.1 DATA SYSTEMS & SOFTWARE INC. AND SUBSIDIARIES Calculation of Primary Earnings Per Common Share Three months ended March 31, --------------------------- 1996 1997 ---------- ----------- Net income $ 754,673 $(3,396,021) ========== =========== Weighted average number of: Common shares outstanding 7,281,574 7,369,178 Dilutive common equivalents 28,027 2,139 ---------- ----------- Total 7,309,601 7,371,317 ========== =========== Earnings per share $ 0.10 $ (0.46) ========== =========== Earnings per share assuming full dilution are identical to primary earnings per share.