PSTL vs SPY: Correlation
Measured on weekly returns over the past three years, Postal Realty Trust, Inc. (PSTL) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.20, a weak link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PSTL and SPY?
On 3 years of weekly data the PSTL/SPY correlation comes out at 0.20, weak. The relationship has been stable: the 1-year correlation (0.19) sits close to the 3-year figure. The 5-year figure is 0.35, and annualized covariance runs at 64.8 %².
Out of 13 assets tracked against PSTL, SPY lands near the bottom at #9. The last year tells two different stories: PSTL led by 37.2 percentage points, +57.8% for PSTL against +20.6% for SPY. Note the risk asymmetry: PSTL runs 1.5 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.
PSTL vs SPY: side by side
| PSTL (Postal Realty Trust, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +57.8% | +20.6% |
| 5-year return | +61.4% | +82.4% |
| Volatility (ann.) | 22.1% | 14.5% |
| Beta vs S&P 500 | 0.31 | 1.00 |
| Max drawdown (3Y) | -13.6% | -18.8% |
| Market cap | $0.9B | – |
| P/E (trailing) | 44.1 | – |
| Dividend yield | 4.11% | 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 | PSTL | SPY |
|---|---|---|
| 2022 | -22.4% | -18.2% |
| 2023 | +6.9% | +26.2% |
| 2024 | -4.1% | +24.9% |
| 2025 | +32.7% | +17.7% |
| 2026 | +50.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PSTL and SPY good diversifiers for each other?
A fair diversifier. At 0.20, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between PSTL and SPY?
As of 2026-08-27, the correlation of weekly returns between PSTL and SPY is 0.20 over 3 years, 0.19 over 1 year and 0.35 over 5 years.
Is SPY a good diversifier for PSTL?
A fair diversifier. At 0.20, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.20 mean?
On the −1 to +1 scale, 0.20 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: PSTL correlations · SPY correlations
