ALT vs XBI: Correlation
How closely do Altimmune, Inc. (ALT) and SPDR S&P Biotech ETF (XBI) trade together? Their weekly returns over three years give a correlation of 0.46, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ALT and XBI?
Over the past 3 years, ALT and XBI moved with a correlation of 0.46, which is moderate. Little has changed lately, as the 1-year reading of 0.53 lands near the 3-year figure. Over 5 years the correlation is 0.39, and the annualized covariance of weekly returns is 1191.2 %².
In ALT's tracked universe of 13 assets, XBI sits right near the top at #3. The last year tells two different stories: XBI led by 98.9 percentage points, -11.7% for ALT against +87.2% for XBI. Note the risk asymmetry: ALT runs 3.4 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.
ALT vs XBI: side by side
| ALT (Altimmune, Inc.) | XBI (SPDR S&P Biotech ETF) | |
|---|---|---|
| 1-year return | -11.7% | +87.2% |
| 5-year return | -77.0% | +28.6% |
| Volatility (ann.) | 94.4% | 27.7% |
| Beta vs S&P 500 | 1.91 | 1.09 |
| Max drawdown (3Y) | -81.2% | -33.0% |
| Market cap | $0.6B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | – |
| Sector / category | US Listed | ETF · Thematic |
Year-by-year returns
| Year | ALT | XBI |
|---|---|---|
| 2022 | +79.6% | -25.9% |
| 2023 | -31.6% | +7.6% |
| 2024 | -35.9% | +1.0% |
| 2025 | -49.9% | +35.9% |
| 2026 | -10.2% | +38.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ALT and XBI good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.46 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between ALT and XBI?
Using weekly returns as of 2026-08-27: 0.46 over 3 years, with 0.53 over the last year and 0.39 over 5 years.
Is XBI a good diversifier for ALT?
Yes, to a useful degree: a correlation of 0.46 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.46 mean?
On the −1 to +1 scale, 0.46 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: ALT correlations · XBI correlations
