GWH vs SPY: Correlation
ESS Tech, Inc. (GWH) and SPDR S&P 500 ETF Trust (SPY) show a weak relationship: their 3-year correlation of weekly returns is 0.13.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are GWH and SPY?
On 3 years of weekly data the GWH/SPY correlation comes out at 0.13, weak. Lately the two have drifted apart, with the 1-year correlation at -0.12 versus 0.13 over 3 years. The 5-year figure is 0.19, and annualized covariance runs at 230.9 %².
SPY is close to the least connected end of GWH's tracked universe, ranking #8 of 12. Their recent paths diverged sharply: over the last 12 months SPY outperformed by 96.8 percentage points (-76.2% for GWH against +20.6% for SPY). One caveat on sizing: GWH is 8.4 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.
GWH vs SPY: side by side
| GWH (ESS Tech, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -76.2% | +20.6% |
| 5-year return | -99.8% | +82.4% |
| Volatility (ann.) | 122.3% | 14.5% |
| Beta vs S&P 500 | 1.11 | 1.00 |
| Max drawdown (3Y) | -98.8% | -18.8% |
| Market cap | – | – |
| 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 | GWH | SPY |
|---|---|---|
| 2022 | -78.8% | -18.2% |
| 2023 | -53.1% | +26.2% |
| 2024 | -65.6% | +24.9% |
| 2025 | -68.0% | +17.7% |
| 2026 | -80.9% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are GWH and SPY good diversifiers for each other?
By historical standards, yes. A correlation of 0.13 means the two rarely move for the same reasons.
FAQ
What is the correlation between GWH and SPY?
The GWH/SPY correlation stands at 0.13 on a 3-year window (1 year: -0.12, 5 years: 0.19), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for GWH?
By historical standards, yes. A correlation of 0.13 means the two rarely move for the same reasons.
What does a correlation of 0.13 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: GWH correlations · SPY correlations
