ASND vs IBB: Correlation
How closely do Ascendis Pharma A/S (ASND) and iShares Biotechnology ETF (IBB) trade together? Their weekly returns over three years give a correlation of 0.38, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ASND and IBB?
On 3 years of weekly data the ASND/IBB correlation comes out at 0.38, moderate. The past 12 months show a tighter link (0.54) than the 3-year average (0.38). The 5-year figure is 0.40, and annualized covariance runs at 314.3 %².
By 3-year correlation, IBB places #4 of the 11 assets tracked against ASND. Their recent paths diverged sharply: over the last 12 months IBB outperformed by 26.2 percentage points (+29.2% for ASND against +55.4% for IBB). Note the risk asymmetry: ASND runs 1.9 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.
ASND vs IBB: side by side
| ASND (Ascendis Pharma A/S) | IBB (iShares Biotechnology ETF) | |
|---|---|---|
| 1-year return | +29.2% | +55.4% |
| 5-year return | +61.6% | +26.6% |
| Volatility (ann.) | 40.2% | 20.7% |
| Beta vs S&P 500 | 0.69 | 0.81 |
| Max drawdown (3Y) | -29.2% | -24.9% |
| Market cap | $16.4B | – |
| P/E (trailing) | 19.1 | – |
| 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 | ASND | IBB |
|---|---|---|
| 2022 | -9.2% | -13.7% |
| 2023 | +3.1% | +3.8% |
| 2024 | +9.3% | -2.4% |
| 2025 | +54.9% | +28.0% |
| 2026 | +16.9% | +27.4% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
ASND represents 1.07% of IBB's portfolio, so part of any move in IBB is ASND itself, and the correlation between them is partly mechanical.
Are ASND and IBB good diversifiers for each other?
A fair diversifier. At 0.38, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
FAQ
What is the correlation between ASND and IBB?
Using weekly returns as of 2026-08-27: 0.38 over 3 years, with 0.54 over the last year and 0.40 over 5 years.
Is IBB a good diversifier for ASND?
A fair diversifier. At 0.38, enough of each asset's movement is its own that the pair has smoothed outcomes historically.
What does a correlation of 0.38 mean?
A reading of 0.38 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/asnd-vs-ibb.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/asnd-vs-ibb/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: ASND correlations · IBB correlations
