Basic EPS is computed by dividing net income available to common stockholders by the weighted-average common shares outstanding for the period. Diluted EPS is computed by dividing net income by the weighted-average number of common shares outstanding and dilutive potential common shares for the period. Potential common shares include the weighted-average dilutive effects of stock-based awards and shares underlying our Convertible Senior Notes (the "Convertible Notes").

For the first half of fiscal 2026, our Convertible Notes, described in Note 13, "Long-Term Debt", had no impact on the calculation of dilutive potential common shares, as the price of our common stock did not exceed the conversion price. For the first half of fiscal 2025, the Convertible Notes had a dilution impact on the dilutive potential common shares, which was calculated using the if-converted method. The dilution impact was due to the price of our common stock exceeding the conversion price. The related capped call transactions (the "Capped Call Transactions") for all of these periods were excluded from the calculation of dilutive potential common shares as their effect is anti-dilutive. For the second quarters and first halves of fiscal 2026 and 2025, no options were excluded from the calculation of dilutive potential common shares.


	Three Months Ended				Six Months Ended
	March 29, 2026		March 30, 2025		March 29, 2026		March 30, 2025

Net income attributable to Tetra Tech	$	93,623	$	5,388	$	198,651	$	6,135

Weighted-average common shares outstanding – basic	260,144		265,728		260,635		266,819
Effect of dilutive stock options and unvested restricted stock	1,775		1,711		1,848		1,936
Shares issuable assuming conversion of convertible notes	—		—		—		936
Weighted-average common shares outstanding – diluted	261,919		267,439		262,483		269,691

Earnings per share attributable to Tetra Tech:
Basic	$	0.36	$	0.02	$	0.76	$	0.02
Diluted	$	0.36	$	0.02	$	0.76	$	0.02