FSTR vs IOSP: Correlation
Measured on weekly returns over the past three years, L.B. Foster Company (FSTR) and Innospec Inc. (IOSP) carry a correlation of 0.48, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are FSTR and IOSP?
On 3 years of weekly data the FSTR/IOSP correlation comes out at 0.48, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.32 versus 0.48 over 3 years. The 5-year figure is 0.35, and annualized covariance runs at 591.0 %².
Within FSTR's tracked universe of 16 assets, IOSP comes in at #4 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months FSTR outperformed by 31.5 percentage points (+42.8% for FSTR against +11.3% for IOSP). One caveat on sizing: FSTR is 1.7 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.
FSTR vs IOSP: side by side
| FSTR (L.B. Foster Company) | IOSP (Innospec Inc.) | |
|---|---|---|
| 1-year return | +42.8% | +11.3% |
| 5-year return | +119.1% | +10.2% |
| Volatility (ann.) | 46.4% | 26.6% |
| Beta vs S&P 500 | 1.23 | 0.94 |
| Max drawdown (3Y) | -45.9% | -48.4% |
| Market cap | $0.4B | $2.3B |
| P/E (trailing) | 35.4 | 19.5 |
| Dividend yield | 0.00% | 1.87% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | FSTR | IOSP |
|---|---|---|
| 2022 | -29.6% | +15.2% |
| 2023 | +127.2% | +21.5% |
| 2024 | +22.3% | -9.6% |
| 2025 | +0.2% | -28.9% |
| 2026 | +40.4% | +26.0% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are FSTR and IOSP good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.48 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between FSTR and IOSP?
As of 2026-08-27, the correlation of weekly returns between FSTR and IOSP is 0.48 over 3 years, 0.32 over 1 year and 0.35 over 5 years.
Is IOSP a good diversifier for FSTR?
Yes, to a useful degree: a correlation of 0.48 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.48 mean?
On the −1 to +1 scale, 0.48 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.
Use this data
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Related comparisons
Hubs: FSTR correlations · IOSP correlations
