White Mountains Insurance Group WTM Casualty-Active — 9
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Where this comes from
Reported directly by White Mountains Insurance Group in its filing.
Tagged under the XBRL concept us-gaap:ShortdurationInsuranceContractsHistoricalClaimsDurationYearNine.
The official record: White Mountains Insurance Group’s 10-K, filed February 27, 2026, on SEC EDGAR. View the filing →
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Questions, answered.
- What is White Mountains Insurance Group's casualty-active — 9?
- White Mountains Insurance Group (WTM) reported casualty-active — 9 of 4.2% in Q4 2025.
- How has White Mountains Insurance Group's casualty-active — 9 changed year-over-year?
- White Mountains Insurance Group's casualty-active — 9 increased by 13.5% year-over-year, from 3.7% to 4.2%.
- What does casualty-active — 9 mean?
- Represents the cumulative adjustment to prior period loss reserves for the Casualty-Active segment. It serves as a performance indicator for the segment's historical underwriting discipline and reserve management strategy.