v3.25.1
Earnings Per Share
 3 Months Ended
Mar. 31, 2025
Earnings Per Share [Abstract]  
Earnings Per Share Earnings Per Share
 
White Mountains calculates earnings per share using the two-class method, which allocates earnings between common shares and unvested restricted common shares. Both classes of shares participate equally in dividends and earnings on a per share basis. Basic earnings per share amounts are based on the weighted average number of common shares outstanding adjusted for unvested restricted common shares.
The following table presents the Company’s computation of earnings per share from continuing operations for the three months ended March 31, 2025 and 2024.
Three Months Ended March 31,
 20252024
Basic and diluted earnings per share numerators (in millions): 
Net income (loss) attributable to White Mountains’s common shareholders$33.9 $236.4 
Allocation of (earnings) losses to participating restricted common shares (1)
(.3)(2.7)
Basic and diluted earnings (losses) per share numerators $33.6 $233.7 
Basic earnings per share denominators (in thousands):
Total average common shares outstanding during the period2,567.0 2,559.7 
Average unvested restricted common shares (2)
(26.1)(28.6)
Basic earnings (losses) per share denominator2,540.9 2,531.1 
Diluted earnings per share denominator (in thousands):
Total average common shares outstanding during the period2,567.0 2,559.7 
Average unvested restricted common shares (2)
(26.1)(28.6)
Diluted earnings (losses) per share denominator2,540.9 2,531.1 
Basic and diluted earnings per share (in dollars):
Distributed earnings - dividends declared and paid$1.00 $1.00 
Undistributed earnings (losses)12.19 91.33 
Basic and diluted earnings (losses) per share $13.19 $92.33 
(1) Restricted shares issued by White Mountains receive dividends, and therefore, are considered participating securities.
(2) Restricted shares outstanding vest upon a stated date. See Note 12 — “Employee Share-Based Incentive Compensation Plans.”

The following table presents the undistributed net earnings (losses) for the three months ended March 31, 2025 and 2024.
Three Months Ended March 31,
Millions20252024
Undistributed net earnings:
Net income (loss) attributable to White Mountains’s common shareholders,
   net of restricted common share amounts		$33.6 $233.7 
Dividends declared, net of restricted common share amounts (1)
(2.5)(2.5)
Total undistributed net earnings (losses), net of restricted common share amounts$31.1 $231.2 
(1) Restricted shares issued by White Mountains receive dividends, and therefore, are considered participating securities.