AEHR vs SPY: Correlation
How closely do Aehr Test Systems (AEHR) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.34, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are AEHR and SPY?
Over the past 3 years, AEHR and SPY moved with a correlation of 0.34, which is moderate. Lately the two have moved closer together, with the 1-year correlation at 0.54 versus 0.34 over 3 years. Over 5 years the correlation is 0.41, and the annualized covariance of weekly returns is 486.0 %².
Out of 11 assets tracked against AEHR, SPY lands near the bottom at #8. The last year tells two different stories: AEHR led by 251.7 percentage points, +272.3% for AEHR against +20.6% for SPY. One caveat on sizing: AEHR is 6.7 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.
AEHR vs SPY: side by side
| AEHR (Aehr Test Systems) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +272.3% | +20.6% |
| 5-year return | +1209.1% | +82.4% |
| Volatility (ann.) | 97.6% | 14.5% |
| Beta vs S&P 500 | 2.33 | 1.00 |
| Max drawdown (3Y) | -87.2% | -18.8% |
| Market cap | $3.0B | – |
| 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 | AEHR | SPY |
|---|---|---|
| 2022 | -16.9% | -18.2% |
| 2023 | +32.0% | +26.2% |
| 2024 | -37.3% | +24.9% |
| 2025 | +21.4% | +17.7% |
| 2026 | +348.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are AEHR and SPY good diversifiers for each other?
Reasonably. At 0.34, AEHR and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between AEHR and SPY?
The AEHR/SPY correlation stands at 0.34 on a 3-year window (1 year: 0.54, 5 years: 0.41), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for AEHR?
Reasonably. At 0.34, AEHR and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.34 mean?
On the −1 to +1 scale, 0.34 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: AEHR correlations · SPY correlations
