13. Net (Loss) Income per Common Share Attributable to Fortitude Shareholders:

Basic earnings per common share is calculated based on the weighted average number of common shares outstanding for the period. Diluted earnings per common share is calculated based on the assumption that stock options and other dilutive securities outstanding, which have an exercise price less than the average market price of the Company’s common shares during the period, would have been exercised on the later of the beginning of the period or the date granted and that the funds obtained from the exercise were used to purchase common shares at the average market price during the period.

The effect of the Company’s dilutive securities is calculated using the treasury stock method and only those instruments that result in a reduction in net income per common share are included in the calculation. Options to purchase 100,000 shares of common stock at weighted average prices of $5.84 and 792,000 restricted stock units (“RSUs”) at a weighted average fair value of $4.65 were outstanding as of March 31, 2026 but had no dilutive effect due to the net loss. As of March 31, 2025, potentially dilutive securities representing 100,000 shares of common stock were excluded from the computation of diluted earnings per share because their effect would have been antidilutive.

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Basic and diluted net (loss) income per common share attributable to Fortitude Shareholders is calculated as follows:

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