Exhibit 11
Tetra Tech, Inc.
Computation of Net Income Per Common Share
(Unaudited)
Three Months Ended Six Months Ended
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April 4, March 29, April 4, March 29,
1999 1998 1999 1998
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Basic:
Common stock outstanding,
beginning of period 28,684,117 27,840,926 26,630,600 25,892,818
Stock options exercised 83,226 131,266 136,590 154,943
Stock purchase plan issuance -- -- 153 --
Issuance of common stock 1,295,185 77,008 1,295,185 2,001,757
Payment of fractional shares -- -- -- (318)
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Common stock outstanding,
end of period 30,062,528 28,049,200 30,062,528 28,049,200
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Weighted average common
stock outstanding
during the period 29,435,000 27,905,000 29,045,000 27,561,000
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Net income as reported in
condensed consolidated
financial statements $ 6,462,000 $ 4,521,000 $11,889,000 $ 8,571,000
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Basic Earnings Per Share $ 0.22 $ 0.16 $ 0.41 $ 0.31
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Diluted:
Weighted average common
stock outstanding
during the period 29,435,000 27,905,000 29,045,000 27,561,000
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 1,976,000 1,051,000 2,016,000 1,334,000
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Total 31,411,000 28,956,000 31,061,000 28,895,000
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Net income as reported in
condensed consolidated
financial statements $ 6,462,000 $ 4,521,000 $11,889,000 $ 8,571,000
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Diluted Earnings Per Share $ 0.21 $ 0.16 $ 0.38 $ 0.30
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See accompanying Notes to Condensed Consolidated Financial Statements.