JMSB vs SPY: Correlation
How closely do John Marshall Bancorp, Inc. (JMSB) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.30, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are JMSB and SPY?
Across a 3-year window, the weekly returns of JMSB and SPY correlate at 0.30, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.00 versus 0.30 over 3 years. Stretching to 5 years gives 0.16, with an annualized covariance of 136.6 %².
Out of 10 assets tracked against JMSB, SPY lands near the bottom at #6. The trailing year gives SPY the advantage: +13.8% versus +20.6%, a 6.8-point spread. Risk is not evenly split, since JMSB carries 2.2 times the volatility of the other side.
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.
JMSB vs SPY: side by side
| JMSB (John Marshall Bancorp, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | +13.8% | +20.6% |
| 5-year return | +32.1% | +82.4% |
| Volatility (ann.) | 31.7% | 14.5% |
| Beta vs S&P 500 | 0.65 | 1.00 |
| Max drawdown (3Y) | -45.4% | -18.8% |
| Market cap | $0.3B | – |
| P/E (trailing) | 13.1 | – |
| Dividend yield | 0.79% | 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 | JMSB | SPY |
|---|---|---|
| 2022 | +45.8% | -18.2% |
| 2023 | -20.8% | +26.2% |
| 2024 | -9.7% | +24.9% |
| 2025 | +1.2% | +17.7% |
| 2026 | +14.5% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are JMSB and SPY good diversifiers for each other?
Reasonably. At 0.30, JMSB and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between JMSB and SPY?
Using weekly returns as of 2026-08-27: 0.30 over 3 years, with 0.00 over the last year and 0.16 over 5 years.
Is SPY a good diversifier for JMSB?
Reasonably. At 0.30, JMSB and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.30 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: JMSB correlations · SPY correlations
