WTM vs XLO: Correlation
How closely do White Mountains Insurance Group, Ltd. (WTM) and Xilio Therapeutics, Inc. (XLO) trade together? Their weekly returns over three years give a correlation of -0.21, which is negative.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are WTM and XLO?
On 3 years of weekly data the WTM/XLO correlation comes out at -0.21, negative, meaning they tend to move in opposite directions. Recent behaviour matches the longer record: -0.17 over 1 year against -0.21 over 3. The 5-year figure is -0.07, and annualized covariance runs at -423.6 %².
Among the 10 assets we track against WTM, XLO sits near the bottom by co-movement, at rank #9. Their recent paths diverged sharply: over the last 12 months WTM outperformed by 21.3 percentage points (+15.3% for WTM against -6.0% for XLO). One caveat on sizing: XLO is 4.7 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
WTM vs XLO: side by side
| WTM (White Mountains Insurance Group, Ltd.) | XLO (Xilio Therapeutics, Inc.) | |
|---|---|---|
| 1-year return | +15.3% | -6.0% |
| 5-year return | +90.5% | -96.0% |
| Volatility (ann.) | 20.6% | 96.4% |
| Beta vs S&P 500 | 0.23 | -0.07 |
| Max drawdown (3Y) | -18.0% | -82.8% |
| Market cap | $5.1B | $0.1B |
| P/E (trailing) | 4.9 | – |
| Dividend yield | 0.05% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | WTM | XLO |
|---|---|---|
| 2022 | +39.6% | -83.2% |
| 2023 | +6.5% | -79.6% |
| 2024 | +29.3% | +73.6% |
| 2025 | +6.9% | -33.0% |
| 2026 | +2.4% | +0.6% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are WTM and XLO good diversifiers for each other?
By historical standards, yes. A correlation of -0.21 means the two rarely move for the same reasons.
FAQ
What is the correlation between WTM and XLO?
As of 2026-08-27, the correlation of weekly returns between WTM and XLO is -0.21 over 3 years, -0.17 over 1 year and -0.07 over 5 years.
Is XLO a good diversifier for WTM?
By historical standards, yes. A correlation of -0.21 means the two rarely move for the same reasons.
What does a correlation of -0.21 mean?
On the −1 to +1 scale, -0.21 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
Use this data
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The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: WTM correlations · XLO correlations
