CMPS vs SPY: Correlation
How closely do COMPASS Pathways Plc - American Depository Shares (CMPS) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.31, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CMPS and SPY?
Over the past 3 years, CMPS and SPY moved with a correlation of 0.31, which is moderate. Recent behaviour matches the longer record: 0.35 over 1 year against 0.31 over 3. Over 5 years the correlation is 0.33, and the annualized covariance of weekly returns is 358.5 %².
Among the 13 assets we track against CMPS, SPY sits near the bottom by co-movement, at rank #9. Their recent paths diverged sharply: over the last 12 months CMPS outperformed by 189.6 percentage points (+210.2% for CMPS against +20.6% for SPY). Note the risk asymmetry: CMPS runs 5.5 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
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.
CMPS vs SPY: side by side
| CMPS (COMPASS Pathways Plc - American Depository Shares) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +210.2% | +20.6% |
| 5-year return | -55.2% | +82.4% |
| Volatility (ann.) | 79.7% | 14.5% |
| Beta vs S&P 500 | 1.72 | 1.00 |
| Max drawdown (3Y) | -81.0% | -18.8% |
| Market cap | $2.0B | – |
| 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 | CMPS | SPY |
|---|---|---|
| 2022 | -63.7% | -18.2% |
| 2023 | +9.0% | +26.2% |
| 2024 | -56.8% | +24.9% |
| 2025 | +82.5% | +17.7% |
| 2026 | +112.2% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CMPS and SPY good diversifiers for each other?
Reasonably. At 0.31, CMPS and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between CMPS and SPY?
Using weekly returns as of 2026-08-27: 0.31 over 3 years, with 0.35 over the last year and 0.33 over 5 years.
Is SPY a good diversifier for CMPS?
Reasonably. At 0.31, CMPS and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.31 mean?
A reading of 0.31 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: CMPS correlations · SPY correlations
