1 EXHIBIT 11-20 DTE ENERGY COMPANY BASIC AND DILUTED EARNINGS PER SHARE OF COMMON STOCK Three Months Nine Months Ended Ended September 30, 2000 September 30, 2000 ------------------ ------------------ (Thousands, except per share amounts) BASIC: Net income....................................................... $ 103,784 $329,050 Weighted average number of common shares outstanding (a)......................................... 142,655 143,272 Earnings per share of common stock based on weighted average number of shares outstanding.......................................... $ 0.73 $ 2.30 DILUTED: Net income....................................................... $ 103,784 $329,050 Weighted average number of common shares outstanding (a)......................................... 142,655 143,272 Incremental shares from assumed exercise of options..................................................... 181 88 ------------ -------- 142,836 143,360 ============ ======== Earnings per share of common stock assuming exercise of options................................... $ 0.73 $ 2.30 - -------------------------- (a) Based on a daily average.