CASS vs SPY: Correlation
Measured on weekly returns over the past three years, Cass Information Systems, Inc (CASS) and SPDR S&P 500 ETF Trust (SPY) carry a correlation of 0.41, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CASS and SPY?
Across a 3-year window, the weekly returns of CASS and SPY correlate at 0.41, moderate. The link has loosened recently: the 1-year correlation (0.25) runs below the 3-year figure (0.41). Stretching to 5 years gives 0.41, with an annualized covariance of 138.0 %².
Out of 10 assets tracked against CASS, SPY lands near the bottom at #6. The last year tells two different stories: CASS led by 15.5 percentage points, +36.1% for CASS against +20.6% for SPY. Note the risk asymmetry: CASS runs 1.6 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.
CASS vs SPY: side by side
| CASS (Cass Information Systems, Inc) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +36.1% | +20.6% |
| 5-year return | +45.6% | +82.4% |
| Volatility (ann.) | 23.2% | 14.5% |
| Beta vs S&P 500 | 0.66 | 1.00 |
| Max drawdown (3Y) | -20.5% | -18.8% |
| Market cap | $0.7B | – |
| P/E (trailing) | 20.7 | – |
| Dividend yield | 2.23% | 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 | CASS | SPY |
|---|---|---|
| 2022 | +20.0% | -18.2% |
| 2023 | +1.1% | +26.2% |
| 2024 | -6.7% | +24.9% |
| 2025 | +4.5% | +17.7% |
| 2026 | +38.8% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CASS and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.41 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between CASS and SPY?
The CASS/SPY correlation stands at 0.41 on a 3-year window (1 year: 0.25, 5 years: 0.41), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for CASS?
Yes, to a useful degree: a correlation of 0.41 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.41 mean?
A reading of 0.41 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
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Related comparisons
Hubs: CASS correlations · SPY correlations
