IBB vs SRPT: Correlation
iShares Biotechnology ETF (IBB) and Sarepta Therapeutics, Inc. (SRPT) show a moderate relationship: their 3-year correlation of weekly returns is 0.40.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and SRPT?
Across a 3-year window, the weekly returns of IBB and SRPT correlate at 0.40, moderate. Little has changed lately, as the 1-year reading of 0.48 lands near the 3-year figure. Stretching to 5 years gives 0.38, with an annualized covariance of 627.0 %².
Among the 168 assets we track against IBB, SRPT ranks #145 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months IBB outperformed by 35.9 percentage points (+55.4% for IBB against +19.5% for SRPT). One caveat on sizing: SRPT is 3.7 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.
IBB vs SRPT: side by side
| IBB (iShares Biotechnology ETF) | SRPT (Sarepta Therapeutics, Inc.) | |
|---|---|---|
| 1-year return | +55.4% | +19.5% |
| 5-year return | +26.6% | -71.5% |
| Volatility (ann.) | 20.7% | 75.7% |
| Beta vs S&P 500 | 0.81 | 1.09 |
| Max drawdown (3Y) | -24.9% | -92.7% |
| Market cap | – | $2.3B |
| 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 | SRPT |
|---|---|---|
| 2022 | -13.7% | +43.9% |
| 2023 | +3.8% | -25.6% |
| 2024 | -2.4% | +26.1% |
| 2025 | +28.0% | -82.3% |
| 2026 | +27.4% | +0.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
Keep in mind that IBB holds SRPT at a 0.14% weight, which makes a slice of this correlation mechanical rather than coincidental.
Are IBB and SRPT good diversifiers for each other?
A fair diversifier. At 0.40, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between IBB and SRPT?
Using weekly returns as of 2026-08-27: 0.40 over 3 years, with 0.48 over the last year and 0.38 over 5 years.
Is SRPT a good diversifier for IBB?
A fair diversifier. At 0.40, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.40 mean?
On the −1 to +1 scale, 0.40 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-srpt.json
Embed this badge (it refreshes with the data), with attribution:
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Related comparisons
Hubs: IBB correlations · SRPT correlations
