Exhibit 11 WASTE INDUSTRIES, INC. COMPUTATION RE: EARNINGS PER SHARE Pro forma (1) Pro forma (1) Three Months Ended Nine Months Ended September 30, September 30, ------------------------------- ------------------------------- 1997 1998 1997 1998 ---------- ---------- ---------- ---------- Net income $2,056,414 $2,820,655 $5,084,008 $7,668,656 ========== ========== ========== ========== Weighted average number of common shares issued and outstanding - Basic 12,580,900 12,816,743 11,401,613 12,706,715 Common stock equivalents - Options for common stock 526,000 663,802 526,000 601,201 ---------- ---------- ---------- ---------- Weighted average common stock equivalents 13,106,900 13,480,545 11,927,613 13,307,916 Less treasury shares to be repurchased (127,916) (262,250) (143,292) (212,343) ---------- ---------- ---------- ---------- Weighted average shares outstanding - Diluted 12,978,984 13,218,295 11,784,321 13,095,573 ---------- ---------- ---------- ---------- Basic earnings per share $0.16 $0.22 $0.45 $0.60 ========== ========== ========== ========== Diluted earnings per share $0.16 $0.21 $0.43 $0.59 ========== ========== ========== ========== (1) Pro forma basic and diluted earnings per share computations are based on the weighted-average common stock outstanding and include the dilutive effect of stock options using the treasury stock method (using the initial offering price of $13.50 per share for periods prior to the initial public offering. Common stock outstanding used to compute the weighted-average shares was retroactively adjusted for the 1996 exchange of shares resulting from the merger of affiliated companies, for the 1997 conversion of nonvoting to voting stock, for the 1997 1-for-2.5 reverse stock split, for the acquisition of entities under common control during the quarter ended March 31, 1998, and for the merger with an entity under the pooling of interest method during the quarter ended September 30,1998. The Company's S Corporation status was terminated on May 8, 1997 and, accordingly, the Company became fully subject to federal and state income taxes on May 9, 1997. Pro forma net income and earnings per share amounts have been computed as if the Company was subject to federal and all applicable state corporate income taxes for the three months and nine months ended September 30, 1997.