BCAB vs IBB: Correlation
Measured on weekly returns over the past three years, BioAtla, Inc. (BCAB) and iShares Biotechnology ETF (IBB) carry a correlation of 0.45, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BCAB and IBB?
Across a 3-year window, the weekly returns of BCAB and IBB correlate at 0.45, moderate. The link has loosened recently: the 1-year correlation (0.24) runs below the 3-year figure (0.45). Stretching to 5 years gives 0.43, with an annualized covariance of 1110.8 %².
Within BCAB's tracked universe of 11 assets, IBB comes in at #4 by 3-year correlation. Correlation aside, the last 12 months split them widely, with IBB ahead by 141.4 points (-86.0% versus +55.4%). Risk is not evenly split, since BCAB carries 5.8 times the volatility of the other side.
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.
BCAB vs IBB: side by side
| BCAB (BioAtla, Inc.) | IBB (iShares Biotechnology ETF) | |
|---|---|---|
| 1-year return | -86.0% | +55.4% |
| 5-year return | -99.8% | +26.6% |
| Volatility (ann.) | 119.3% | 20.7% |
| Beta vs S&P 500 | 2.75 | 0.81 |
| Max drawdown (3Y) | -98.4% | -24.9% |
| Market cap | – | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 0.22% |
| Expense ratio | – | 0.44% |
| Assets under management | – | $9.2B |
| Sector / category | US Listed | ETF · Thematic |
IBB, iShares's Health fund, carries $9.2B under management, 235 holdings, a 0.44% expense ratio, a 0.22% trailing dividend yield.
Year-by-year returns
| Year | BCAB | IBB |
|---|---|---|
| 2022 | -58.0% | -13.7% |
| 2023 | -70.2% | +3.8% |
| 2024 | -76.0% | -2.4% |
| 2025 | -3.9% | +28.0% |
| 2026 | -88.9% | +27.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BCAB and IBB good diversifiers for each other?
A fair diversifier. At 0.45, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between BCAB and IBB?
The BCAB/IBB correlation stands at 0.45 on a 3-year window (1 year: 0.24, 5 years: 0.43), computed from weekly returns as of 2026-08-27.
Is IBB a good diversifier for BCAB?
A fair diversifier. At 0.45, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.45 mean?
On the −1 to +1 scale, 0.45 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/bcab-vs-ibb.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/bcab-vs-ibb/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: BCAB correlations · IBB correlations
