ENS vs SPY: Correlation
EnerSys (ENS) and SPDR S&P 500 ETF Trust (SPY) show a moderate relationship: their 3-year correlation of weekly returns is 0.52.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ENS and SPY?
Across a 3-year window, the weekly returns of ENS and SPY correlate at 0.52, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.36 versus 0.52 over 3 years. Stretching to 5 years gives 0.60, with an annualized covariance of 228.7 %².
Within ENS's tracked universe of 11 assets, SPY comes in at #6 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months ENS outperformed by 67.3 percentage points (+87.9% for ENS against +20.6% for SPY). Note the risk asymmetry: ENS runs 2.1 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.
ENS vs SPY: side by side
| ENS (EnerSys) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +87.9% | +20.6% |
| 5-year return | +131.9% | +82.4% |
| Volatility (ann.) | 30.1% | 14.5% |
| Beta vs S&P 500 | 1.09 | 1.00 |
| Max drawdown (3Y) | -28.2% | -18.8% |
| Market cap | $6.9B | – |
| P/E (trailing) | 20.7 | – |
| Dividend yield | 0.54% | 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 | ENS | SPY |
|---|---|---|
| 2022 | -5.6% | -18.2% |
| 2023 | +37.9% | +26.2% |
| 2024 | -7.6% | +24.9% |
| 2025 | +60.3% | +17.7% |
| 2026 | +30.5% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ENS and SPY good diversifiers for each other?
To a limited degree. At 0.52 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
FAQ
What is the correlation between ENS and SPY?
Using weekly returns as of 2026-08-27: 0.52 over 3 years, with 0.36 over the last year and 0.60 over 5 years.
Is SPY a good diversifier for ENS?
To a limited degree. At 0.52 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
What does a correlation of 0.52 mean?
On the −1 to +1 scale, 0.52 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: ENS correlations · SPY correlations
