ACGL vs SPY: Correlation
Measured on weekly returns over the past three years, Arch Capital Group (ACGL) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.19, a weak link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ACGL and SPY?
Over the past 3 years, ACGL and SPY moved with a correlation of 0.19, which is weak. The past 12 months show a weaker link (-0.11) than the 3-year average (0.19). Over 5 years the correlation is 0.31, and the annualized covariance of weekly returns is 58.6 %².
By 3-year correlation, SPY places #23 of the 36 assets tracked against ACGL. Over the last 12 months SPY came out ahead by 12.9 percentage points (+7.7% against +20.6%). The relationship is regime-dependent: the rolling one-year correlation swung between -0.10 and 0.48 over the past three years, so this pair behaves very differently depending on the market environment.
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.
ACGL vs SPY: side by side
| ACGL (Arch Capital Group) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +7.7% | +20.6% |
| 5-year return | +151.8% | +82.4% |
| Volatility (ann.) | 21.5% | 14.5% |
| Beta vs S&P 500 | 0.28 | 1.00 |
| Max drawdown (3Y) | -22.4% | -18.8% |
| Market cap | $33.7B | – |
| P/E (trailing) | 7.9 | – |
| Dividend yield | 0.00% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | Financials | ETF · US Large Cap |
SPY is a Large Blend fund from State Street Investment Management: $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | ACGL | SPY |
|---|---|---|
| 2022 | +41.2% | -18.2% |
| 2023 | +18.3% | +26.2% |
| 2024 | +30.8% | +24.9% |
| 2025 | +3.9% | +17.7% |
| 2026 | +3.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
ACGL represents 0.05% of SPY's portfolio, so part of any move in SPY is ACGL itself, and the correlation between them is partly mechanical.
Are ACGL and SPY good diversifiers for each other?
Yes. With a correlation of 0.19, ACGL and SPY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
FAQ
What is the correlation between ACGL and SPY?
Using weekly returns as of 2026-08-27: 0.19 over 3 years, with -0.11 over the last year and 0.31 over 5 years.
Is SPY a good diversifier for ACGL?
Yes. With a correlation of 0.19, ACGL and SPY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
What does a correlation of 0.19 mean?
A reading of 0.19 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: ACGL correlations · SPY correlations
