1 EXHIBIT 11.0 CONCORD COMMUNICATIONS, INC. Computation of Pro Forma Net Income (Loss) Per Common Share (unaudited) (1) FORM 10-Q, September 30, 1997 (dollars in thousands, except per share data) Three Months Ended Nine Months Ended September 30, September 28, September 30, September 28, ------------------------------ ------------------------------ 1997 1996 1997 1996 ----------- ---------- ---------- ----------- Net Income (Loss) $ 202 $ (881) $ (764) $ (3,676) ----------- ---------- ---------- ----------- Shares used in computing Pro forma Net Income (Loss) Per Common and Common Equivalent Shares outstanding (unaudited): Weighted average common stock outstanding during the period 824,394 791,886 806,942 791,427 Dilutive effect of common stock issued subsequent to June 30, 1997 (2) 263,290 263,290 263,290 263,290 Dilutive effect of common equivalent shares issued subsequent to June 30, 1997 (2) 635,415 635,415 635,415 635,415 Pro forma conversion of redeemable convertible preferred stock to common stock (unaudited) 8,108,258 8,108,258 8,108,258 8,108,258 Weighted average common equivalent shares outstanding during the period 1,062,322 - - - ----------- ---------- ---------- ---------- 10,893,679 9,798,849 9,813,905 9,798,390 =========== ========== ========== ========== Pro forma Net Income (Loss) Per Common Share $ 0.02 $ (0.09) $ (0.08) $ (0.38) =========== ========== ========== ========== (1) Historical net income (loss) per common share has not been separately presented, as the amounts would not be meaningful. (2) Pursuant to Securities and Exchange Commission Staff Accounting Bulletin No. 83, common stock, preferred stock, stock options and warrants issued at prices below the initial public offering price per share ("cheap stock") during the twelve month period immediately preceding the filing date of the Company's Registration Statement for its initial public offering have been included as outstanding for all periods presented until the effective date of the Company's initial public offering. The dilutive effect of the common and common stock equivalents was computed in accordance with the treasury stock method. 22 --