EXHIBIT 11
Tetra Tech, Inc.
Computation of Earnings Per Common Share
(Unaudited)
Three Months Ended
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December 28, December 29,
1997 1996
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Basic:
Common stock outstanding, beginning of
period................................. 20,714,254 17,658,752
Stock options exercised.................. 18,941 18,601
Issuance of common stock................. 1,539,800 127,909
Payment of fractional shares............. (254) --
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Common stock outstanding, end of period.. 22,272,741 17,805,262
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Weighted average shares common
outstanding during the period.......... 21,773,524 17,687,890
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Total................................ 21,773,524 17,687,890
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Net Income as reported in condensed
consolidated financial statements......$ 4,051,000 $ 2,596,000
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Basic Earnings Per Share.................$ 0.19 $ 0.15
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Diluted:
Weighted average shares common
outstanding during the period.......... 21,773,524 $ 17,687,890
Potential common shares under the
treasury stock method assuming the
exercise of options and warrants....... 808,347 673,219
Other potentially dilutive securities:
Convertible Preferred Stock............ 490,705 --
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Total................................ 23,072,576 18,361,109
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Net Income as reported in condensed
consolidated financial statements...... 4,051,000 2,596,000
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Diluted Earnings Per Share...............$ 0.18 $ 0.14
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