EXHIBIT 11
Tetra Tech, Inc.
Computation of Net Income Per Common Share
(Unaudited)
Three Months Ended Nine Months Ended
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June 28, June 29, June 28, June 29,
1998 1997 1998 1997
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Basic:
Common stock outstanding,
beginning of period 22,439,360 18,046,198 20,714,254 17,658,753
Stock options exercised 90,095 55,605 214,049 130,776
Stock purchase plan issuance 92,110 123,231 92,110 123,231
Issuance of common stock -- 2,105,280 1,601,406 2,417,554
Payment of fractional shares -- -- (254) --
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Common stock outstanding,
end of period 22,621,565 20,330,314 22,621,565 20,330,314
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Weighted average common
stock outstanding during
the period 22,517,513 18,542,316 22,204,928 18,025,079
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Net income as reported in
condensed consolidated
financial statements $ 5,493,000 $ 3,644,000 $14,064,000 $ 9,111,000
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Basic Earnings Per Share $ 0.24 $ 0.20 $ 0.63 $ 0.51
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Diluted:
Weighted average common
stock outstanding during
the period 22,517,513 18,542,316 22,204,928 18,025,079
Potential common shares
under the treasury stock
method assuming the
exercise of options and
warrants and the conversion
of preferred stock 843,521 748,216 991,736 622,681
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Total 23,361,034 19,290,533 23,196,664 18,647,760
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Net income as reported in
condensed consolidated
financial statements $ 5,493,000 $ 3,644,000 $14,064,000 $ 9,111,000
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Diluted Earnings Per Share $ 0.24 $ 0.19 $ 0.61 $ 0.49
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See accompanying notes to the condensed consolidated financial statements.