APT vs SPY: Correlation
Measured on weekly returns over the past three years, Alpha Pro Tech, Ltd. (APT) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.22, a weak link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are APT and SPY?
On 3 years of weekly data the APT/SPY correlation comes out at 0.22, weak. The relationship has been stable: the 1-year correlation (0.29) sits close to the 3-year figure. The 5-year figure is 0.20, and annualized covariance runs at 135.4 %².
Out of 12 assets tracked against APT, SPY lands near the bottom at #9. On 12-month performance SPY holds a 7.8-point edge, +12.8% against +20.6%. Note the risk asymmetry: APT runs 2.9 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.
APT vs SPY: side by side
| APT (Alpha Pro Tech, Ltd.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +12.8% | +20.6% |
| 5-year return | -33.5% | +82.4% |
| Volatility (ann.) | 42.0% | 14.5% |
| Beta vs S&P 500 | 0.65 | 1.00 |
| Max drawdown (3Y) | -39.0% | -18.8% |
| Market cap | $0.1B | – |
| P/E (trailing) | 14.0 | – |
| 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 | APT | SPY |
|---|---|---|
| 2022 | -32.7% | -18.2% |
| 2023 | +31.6% | +26.2% |
| 2024 | +0.0% | +24.9% |
| 2025 | -16.1% | +17.7% |
| 2026 | +23.2% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are APT and SPY good diversifiers for each other?
Reasonably. At 0.22, APT and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between APT and SPY?
As of 2026-08-27, the correlation of weekly returns between APT and SPY is 0.22 over 3 years, 0.29 over 1 year and 0.20 over 5 years.
Is SPY a good diversifier for APT?
Reasonably. At 0.22, APT and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.22 mean?
On the −1 to +1 scale, 0.22 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: APT correlations · SPY correlations
