ACHC vs SPY: Correlation
Acadia Healthcare Company, Inc. (ACHC) and SPDR S&P 500 ETF Trust (SPY) show a weak relationship: their 3-year correlation of weekly returns is 0.15.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ACHC and SPY?
Across a 3-year window, the weekly returns of ACHC and SPY correlate at 0.15, weak. The past 12 months show a weaker link (0.04) than the 3-year average (0.15). Stretching to 5 years gives 0.22, with an annualized covariance of 129.3 %².
Out of 10 assets tracked against ACHC, SPY lands near the bottom at #6. The last year tells two different stories: ACHC led by 15.6 percentage points, +36.2% for ACHC against +20.6% for SPY. One caveat on sizing: ACHC is 4.0 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.
ACHC vs SPY: side by side
| ACHC (Acadia Healthcare Company, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +36.2% | +20.6% |
| 5-year return | -54.4% | +82.4% |
| Volatility (ann.) | 58.4% | 14.5% |
| Beta vs S&P 500 | 0.62 | 1.00 |
| Max drawdown (3Y) | -86.6% | -18.8% |
| Market cap | $2.8B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | US Listed | 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 | ACHC | SPY |
|---|---|---|
| 2022 | +35.6% | -18.2% |
| 2023 | -5.5% | +26.2% |
| 2024 | -49.0% | +24.9% |
| 2025 | -64.2% | +17.7% |
| 2026 | +113.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ACHC and SPY good diversifiers for each other?
By historical standards, yes. A correlation of 0.15 means the two rarely move for the same reasons.
FAQ
What is the correlation between ACHC and SPY?
The ACHC/SPY correlation stands at 0.15 on a 3-year window (1 year: 0.04, 5 years: 0.22), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for ACHC?
By historical standards, yes. A correlation of 0.15 means the two rarely move for the same reasons.
What does a correlation of 0.15 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: ACHC correlations · SPY correlations
