SMMT vs SPY: Correlation
How closely do Summit Therapeutics Inc. (SMMT) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.23, which is weak.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SMMT and SPY?
On 3 years of weekly data the SMMT/SPY correlation comes out at 0.23, weak. The past 12 months show a tighter link (0.39) than the 3-year average (0.23). The 5-year figure is 0.03, and annualized covariance runs at 506.9 %².
Out of 13 assets tracked against SMMT, SPY lands near the bottom at #9. Correlation aside, the last 12 months split them widely, with SPY ahead by 62.8 points (-42.2% versus +20.6%). One caveat on sizing: SMMT is 10.4 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.
SMMT vs SPY: side by side
| SMMT (Summit Therapeutics Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -42.2% | +20.6% |
| 5-year return | +78.5% | +82.4% |
| Volatility (ann.) | 150.4% | 14.5% |
| Beta vs S&P 500 | 2.43 | 1.00 |
| Max drawdown (3Y) | -66.1% | -18.8% |
| Market cap | $11.4B | – |
| 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 | SMMT | SPY |
|---|---|---|
| 2022 | +58.0% | -18.2% |
| 2023 | -38.6% | +26.2% |
| 2024 | +583.7% | +24.9% |
| 2025 | -2.0% | +17.7% |
| 2026 | -18.1% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are SMMT and SPY good diversifiers for each other?
Reasonably. At 0.23, SMMT and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between SMMT and SPY?
Using weekly returns as of 2026-08-27: 0.23 over 3 years, with 0.39 over the last year and 0.03 over 5 years.
Is SPY a good diversifier for SMMT?
Reasonably. At 0.23, SMMT and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.23 mean?
On the −1 to +1 scale, 0.23 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.
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Related comparisons
Hubs: SMMT correlations · SPY correlations
