Exhibit 11 ZMAX CORPORATION AND SUBSIDIARY CALCULATION OF BASIC AND DILUTED NET INCOME (LOSS) PER SHARE (UNAUDITED) Three Months Nine Months Ended September 30, Ended September 30, ---------------------------------------------------------------- 1998 1997 1998 1997 ------------- ------------- ------------- ------------- (unaudited) (unaudited) WEIGHTED AVERAGE SHARE CALCULATIONS BASIC WEIGHTED AVERAGE SHARES OUTSTANDING: Weighted average shares of common stock Outstanding 11,729,714 6,458,774 10,805,714 5,558,970 Less: Average number of cancelable shares common stock outstanding (479,801) (479,801) (479,801) (479,801) ------------- ------------- ------------- ------------- Basic weighted average shares outstanding 11,249,913 5,978,973 10,325,913 5,079,169 ============= ============= ============= ============= Diluted weighted average shares outstanding: Basic weighted average shares outstanding: 11,249,913 5,978,973 10,325,913 5,079,169 Treasury stock effect of options and warrants 374 - - - Diluted weighted average shares outstanding: 11,250,287 5,978,973 10,325,913 5,079,169 ============= ============= ============= =============