Exhibit 11
Tetra Tech, Inc.
Computation of Net Income Per Common Share
(Unaudited)
Three Months Ended
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January 3, December 28,
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1999 1997
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Basic:
Common stock outstanding, beginning of period........................... 28,630,600 25,892,818
Stock options exercised................................................. 53,364 23,676
Stock purchase plan issuance............................................ 153
Issuance of common stock................................................ -- 1,924,750
Payment of fractional shares............................................ -- (318)
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Common stock outstanding, end of period................................. 28,684,117 27,840,926
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Weighted average common stock outstanding during the period............. 29,655,622 27,217,905
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Net income as reported in condensed
consolidated financial statements..................................... $ 5,427,000 $ 4,051,000
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Basic Earnings Per Share................................................ $ 0.19 $ 0.15
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Diluted:
Weighted average common stock outstanding during the period............. 29,655,622 27,216,905
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............. 1,054,273 1,626,383
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Total............................................................. 30,709,895 28,843,288
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Net income as reported in condensed consolidated financial statements... $ 5,427,000 $ 4,051,000
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Diluted Earnings Per Share.............................................. $ 0.18 $ 0.14
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See accompanying Notes to Condensed Consolidated Financial Statements.