VIALOG CORPORATION CALCULATION OF SHARES USED IN DETERMINING NET LOSS PER SHARE (Unaudited) Three Months Ended Nine Months Ended September 30, September 30, -------------------- -------------------- 1999 2000 1999 2000 --------- --------- --------- --------- Common stock, beginning of period........................... 8,661,722 9,471,102 3,693,672 9,133,569 Weighted average common shares issued during period, net........ 77,503 25,199 3,933,948 207,631 Common stock options and warrants using the treasury stock method.. -- -- -- -- --------- --------- --------- --------- 8,739,225 9,496,301 7,627,620 9,341,200 ========= ========= ========= ========= Net loss (in thousands)........... $ (2,478) $ (3,731) $ (9,403) $ (6,009) ========= ========= ========= ========= Basic and diluted net loss per share............................ $ (0.28) $ (0.39) $ (1.23) $ (0.64) ========= ========= ========= =========