EXHIBIT 11 SPARTECH CORPORATION AND SUBSIDIARIES COMPUTATION OF NET EARNINGS PER COMMON SHARE (In thousands, except per share amounts) Fiscal Year Ended Oct 30, Oct 31, Nov. 1, 1999 1998 1997 NET EARNINGS Basic net earnings applicable to common shares $43,071 $33,720 $25,493 Add: Distributions on Preferred Securities, 1,280 - - net of tax Diluted net earnings $44,351 $33,720 $25,493 WEIGHTED AVERAGE SHARES OUTSTANDING Weighted average common shares outstanding 27,038 26,807 26,418 Add Shares issuable from assumed exercise of 1,075 - - Preferred Stock Add: Shares issuable from assumed exercise 1,869 1,802 1,420 of options and warrants Diluted weighted average common shares outstanding 29,982 28,609 27,838 NET EARNINGS PER COMMON SHARE Basic $ 1.59 $1.26 $.96 Diluted $ 1.48 $1.18 $.92