PSO vs SPY: Correlation
How closely do Pearson, Plc (PSO) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.20, which is weak.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PSO and SPY?
Over the past 3 years, PSO and SPY moved with a correlation of 0.20, which is weak. The relationship has been stable: the 1-year correlation (0.23) sits close to the 3-year figure. Over 5 years the correlation is 0.21, and the annualized covariance of weekly returns is 64.0 %².
Among the 10 assets we track against PSO, SPY sits near the bottom by co-movement, at rank #6. The trailing year gives SPY the advantage: +15.6% versus +20.6%, a 5.0-point spread. Note the risk asymmetry: PSO 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.
PSO vs SPY: side by side
| PSO (Pearson, Plc) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +15.6% | +20.6% |
| 5-year return | +77.5% | +82.4% |
| Volatility (ann.) | 22.1% | 14.5% |
| Beta vs S&P 500 | 0.31 | 1.00 |
| Max drawdown (3Y) | -30.7% | -18.8% |
| Market cap | $10.0B | – |
| P/E (trailing) | 24.1 | – |
| Dividend yield | 1.56% | 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 | PSO | SPY |
|---|---|---|
| 2022 | +37.7% | -18.2% |
| 2023 | +12.0% | +26.2% |
| 2024 | +34.2% | +24.9% |
| 2025 | -11.2% | +17.7% |
| 2026 | +21.6% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PSO and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.20 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between PSO and SPY?
As of 2026-08-27, the correlation of weekly returns between PSO and SPY is 0.20 over 3 years, 0.23 over 1 year and 0.21 over 5 years.
Is SPY a good diversifier for PSO?
Yes, to a useful degree: a correlation of 0.20 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.20 mean?
A reading of 0.20 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/pso-vs-spy.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/pso-vs-spy/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: PSO correlations · SPY correlations
