FSBW vs PESI: Correlation
How closely do FS Bancorp, Inc. (FSBW) and Perma-Fix Environmental Services, Inc. (PESI) trade together? Their weekly returns over three years give a correlation of 0.42, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are FSBW and PESI?
Across a 3-year window, the weekly returns of FSBW and PESI correlate at 0.42, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.22 versus 0.42 over 3 years. Stretching to 5 years gives 0.30, with an annualized covariance of 686.4 %².
Among the 23 assets we track against FSBW, PESI ranks #18 by 3-year correlation. Correlation aside, the last 12 months split them widely, with PESI ahead by 57.9 points (+3.5% versus +61.4%). One caveat on sizing: PESI is 2.2 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
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.
FSBW vs PESI: side by side
| FSBW (FS Bancorp, Inc.) | PESI (Perma-Fix Environmental Services, Inc.) | |
|---|---|---|
| 1-year return | +3.5% | +61.4% |
| 5-year return | +47.7% | +234.5% |
| Volatility (ann.) | 27.5% | 59.3% |
| Beta vs S&P 500 | 0.69 | 1.10 |
| Max drawdown (3Y) | -26.1% | -58.0% |
| Market cap | $0.3B | $0.4B |
| P/E (trailing) | 9.7 | – |
| Dividend yield | 2.69% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | FSBW | PESI |
|---|---|---|
| 2022 | +2.4% | -44.2% |
| 2023 | +14.1% | +122.7% |
| 2024 | +14.3% | +40.8% |
| 2025 | +3.7% | +13.7% |
| 2026 | +5.9% | +53.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are FSBW and PESI good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.42 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between FSBW and PESI?
As of 2026-08-27, the correlation of weekly returns between FSBW and PESI is 0.42 over 3 years, 0.22 over 1 year and 0.30 over 5 years.
Is PESI a good diversifier for FSBW?
Yes, to a useful degree: a correlation of 0.42 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.42 mean?
A reading of 0.42 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
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[](https://www.pairbook.io/pair/fsbw-vs-pesi/)
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Related comparisons
Hubs: FSBW correlations · PESI correlations
