WST vs XLV: Correlation
West Pharmaceutical Services (WST) and Health Care Select Sector SPDR Fund (XLV) show a moderate relationship: their 3-year correlation of weekly returns is 0.35.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are WST and XLV?
On 3 years of weekly data the WST/XLV correlation comes out at 0.35, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.24 versus 0.35 over 3 years. The 5-year figure is 0.45, and annualized covariance runs at 198.8 %².
By 3-year correlation, XLV places #19 of the 36 assets tracked against WST. On 12-month performance WST holds a 13.6-point edge, +41.1% against +27.5%. Across three years, the rolling one-year figure varied moderately, from 0.08 to 0.55. Note the risk asymmetry: WST runs 2.6 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.
WST vs XLV: side by side
| WST (West Pharmaceutical Services) | XLV (Health Care Select Sector SPDR Fund) | |
|---|---|---|
| 1-year return | +41.1% | +27.5% |
| 5-year return | -22.4% | +37.4% |
| Volatility (ann.) | 38.6% | 14.7% |
| Beta vs S&P 500 | 0.86 | 0.42 |
| Max drawdown (3Y) | -53.8% | -17.1% |
| Market cap | $24.4B | – |
| P/E (trailing) | 44.8 | – |
| Dividend yield | 0.25% | 1.56% |
| Expense ratio | – | 0.08% |
| Assets under management | – | $41.7B |
| Sector / category | Health Care | Sector ETF |
On the fund side, XLV sits in the Health category at State Street Investment Management, with $41.7B under management, 61 holdings, a 0.08% expense ratio, a 1.56% trailing dividend yield.
Year-by-year returns
| Year | WST | XLV |
|---|---|---|
| 2022 | -49.7% | -2.1% |
| 2023 | +50.0% | +2.1% |
| 2024 | -6.8% | +2.5% |
| 2025 | -15.7% | +14.5% |
| 2026 | +26.1% | +11.8% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
WST represents 0.39% of XLV's portfolio, so part of any move in XLV is WST itself, and the correlation between them is partly mechanical.
Are WST and XLV good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.35 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between WST and XLV?
The WST/XLV correlation stands at 0.35 on a 3-year window (1 year: 0.24, 5 years: 0.45), computed from weekly returns as of 2026-08-27.
Is XLV a good diversifier for WST?
Yes, to a useful degree: a correlation of 0.35 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.35 mean?
On the −1 to +1 scale, 0.35 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
$ curl https://www.pairbook.io/api/v1/pairs/wst-vs-xlv.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/wst-vs-xlv/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: WST correlations · XLV correlations
