Exhibit 11
Tetra Tech, Inc.
Computation of Net Income Per Common Share
(Unaudited)
Three Months Ended Nine Months Ended
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July 4, June 28, July 4, June 28,
1999 1998 1999 1998
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Basic:
Common stock outstanding, beginning
of period............................ 37,578,160 35,061,500 35,788,250 32,366,022
Exchanged stock........................ 5,891 -- 143,382
Stock options exercised................ 73,205 140,773 243,943 244,452
Stock purchase plan issuance........... 156,170 143,922 156,361 143,922
Issuance of common stock............... 364,312 -- 1,845,802 2,502,197
Payment of fractional shares........... (45,720) -- (45,720) (398)
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Common stock outstanding, end
of period............................ 38,132,018 35,346,195 38,132,018 35,346,195
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Weighted average common stock
outstanding during the period........ 37,801,477 35,183,614 36,805,123 34,695,200
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Net income as reported in condensed
consolidated financial statements.... $ 8,503,000 $ 5,493,000 $ 20,392,000 $ 14,064,000
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Basic Earnings Per Share............... $ 0.22 $ 0.16 $ 0.55 $ 0.41
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Diluted:
Weighted average common stock
outstanding during the period........ 37,801,477 35,183,614 36,805,123 34,695,200
Potential common shares under the
treasury stock method assuming the
exercise of options and warrants and
the conversion of preferred stock and
exchangeable stock of a subsidiary... 2,343,811 1,318,002 2,460,748 1,549,587
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Total............................ 40,145,288 36,501,616 39,265,871 36,244,787
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Net income as reported in condensed
consolidated financial statements.... $ 8,503,000 $ 5,493,000 $ 20,392,000 $ 14,064,000
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Diluted Earnings Per Share............. $ 0.21 $ 0.15 $ 0.52 $ 0.39
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See accompanying Notes to the Condensed Consolidated Financial Statements.