KALU vs WST: Correlation
How closely do Kaiser Aluminum Corporation (KALU) and West Pharmaceutical Services (WST) trade together? Their weekly returns over three years give a correlation of 0.37, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are KALU and WST?
Across a 3-year window, the weekly returns of KALU and WST correlate at 0.37, moderate. Lately the two have moved closer together, with the 1-year correlation at 0.55 versus 0.37 over 3 years. Stretching to 5 years gives 0.28, with an annualized covariance of 666.2 %².
Out of 17 assets tracked against KALU, WST lands near the bottom at #13. Their recent paths diverged sharply: over the last 12 months KALU outperformed by 62.7 percentage points (+103.8% for KALU against +41.1% for WST).
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.
KALU vs WST: side by side
| KALU (Kaiser Aluminum Corporation) | WST (West Pharmaceutical Services) | |
|---|---|---|
| 1-year return | +103.8% | +41.1% |
| 5-year return | +51.7% | -22.4% |
| Volatility (ann.) | 46.6% | 38.6% |
| Beta vs S&P 500 | 1.72 | 0.86 |
| Max drawdown (3Y) | -48.9% | -53.8% |
| Market cap | $2.6B | $24.4B |
| P/E (trailing) | 11.6 | 44.8 |
| Dividend yield | 1.98% | 0.25% |
| Sector / category | US Listed | Health Care |
Year-by-year returns
| Year | KALU | WST |
|---|---|---|
| 2022 | -16.2% | -49.7% |
| 2023 | -2.1% | +50.0% |
| 2024 | +2.7% | -6.8% |
| 2025 | +70.1% | -15.7% |
| 2026 | +38.5% | +26.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are KALU and WST good diversifiers for each other?
Reasonably. At 0.37, KALU and WST keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between KALU and WST?
The KALU/WST correlation stands at 0.37 on a 3-year window (1 year: 0.55, 5 years: 0.28), computed from weekly returns as of 2026-08-27.
Is WST a good diversifier for KALU?
Reasonably. At 0.37, KALU and WST keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.37 mean?
A reading of 0.37 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/kalu-vs-wst.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/kalu-vs-wst/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: KALU correlations · WST correlations
