IBB vs PLRX: Correlation
Measured on weekly returns over the past three years, iShares Biotechnology ETF (IBB) and Pliant Therapeutics, Inc. (PLRX) carry a correlation of 0.43, a moderate link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and PLRX?
Over the past 3 years, IBB and PLRX moved with a correlation of 0.43, which is moderate. The relationship has been stable: the 1-year correlation (0.42) sits close to the 3-year figure. Over 5 years the correlation is 0.26, and the annualized covariance of weekly returns is 659.5 %².
By 3-year correlation, PLRX places #134 of the 168 assets tracked against IBB. The last year tells two different stories: IBB led by 87.4 percentage points, +55.4% for IBB against -32.0% for PLRX. One caveat on sizing: PLRX is 3.6 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.
IBB vs PLRX: side by side
| IBB (iShares Biotechnology ETF) | PLRX (Pliant Therapeutics, Inc.) | |
|---|---|---|
| 1-year return | +55.4% | -32.0% |
| 5-year return | +26.6% | -93.6% |
| Volatility (ann.) | 20.7% | 74.8% |
| Beta vs S&P 500 | 0.81 | 1.32 |
| Max drawdown (3Y) | -24.9% | -94.7% |
| Market cap | – | $0.1B |
| P/E (trailing) | – | – |
| Dividend yield | 0.22% | 0.00% |
| Expense ratio | 0.44% | – |
| Assets under management | $9.2B | – |
| Sector / category | ETF · Thematic | US Listed |
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 | IBB | PLRX |
|---|---|---|
| 2022 | -13.7% | +43.2% |
| 2023 | +3.8% | -6.3% |
| 2024 | -2.4% | -27.3% |
| 2025 | +28.0% | -90.7% |
| 2026 | +27.4% | -5.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBB and PLRX good diversifiers for each other?
A fair diversifier. At 0.43, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between IBB and PLRX?
As of 2026-08-27, the correlation of weekly returns between IBB and PLRX is 0.43 over 3 years, 0.42 over 1 year and 0.26 over 5 years.
Is PLRX a good diversifier for IBB?
A fair diversifier. At 0.43, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.43 mean?
On the −1 to +1 scale, 0.43 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/ibb-vs-plrx.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/ibb-vs-plrx/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: IBB correlations · PLRX correlations
