BCRX vs XBI: Correlation
How closely do BioCryst Pharmaceuticals, Inc. (BCRX) and SPDR S&P Biotech ETF (XBI) trade together? Their weekly returns over three years give a correlation of 0.41, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BCRX and XBI?
Across a 3-year window, the weekly returns of BCRX and XBI correlate at 0.41, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.19 versus 0.41 over 3 years. Stretching to 5 years gives 0.44, with an annualized covariance of 538.9 %².
By 3-year correlation, XBI places #4 of the 11 assets tracked against BCRX. Their recent paths diverged sharply: over the last 12 months XBI outperformed by 71.4 percentage points (+15.8% for BCRX against +87.2% for XBI). One caveat on sizing: BCRX 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.
BCRX vs XBI: side by side
| BCRX (BioCryst Pharmaceuticals, Inc.) | XBI (SPDR S&P Biotech ETF) | |
|---|---|---|
| 1-year return | +15.8% | +87.2% |
| 5-year return | -37.1% | +28.6% |
| Volatility (ann.) | 47.1% | 27.7% |
| Beta vs S&P 500 | 0.75 | 1.09 |
| Max drawdown (3Y) | -46.0% | -33.0% |
| Market cap | $2.5B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | – |
| Sector / category | US Listed | ETF · Thematic |
Year-by-year returns
| Year | BCRX | XBI |
|---|---|---|
| 2022 | -17.1% | -25.9% |
| 2023 | -47.8% | +7.6% |
| 2024 | +25.5% | +1.0% |
| 2025 | +3.7% | +35.9% |
| 2026 | +26.5% | +38.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BCRX and XBI good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.41 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between BCRX and XBI?
Using weekly returns as of 2026-08-27: 0.41 over 3 years, with 0.19 over the last year and 0.44 over 5 years.
Is XBI a good diversifier for BCRX?
Yes, to a useful degree: a correlation of 0.41 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.41 mean?
On the −1 to +1 scale, 0.41 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/bcrx-vs-xbi.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/bcrx-vs-xbi/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: BCRX correlations · XBI correlations
