IBB vs THW: Correlation
How closely do iShares Biotechnology ETF (IBB) and abrdn World Healthcare Fund Shares of Beneficial Interest (THW) trade together? Their weekly returns over three years give a correlation of 0.70, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and THW?
Over the past 3 years, IBB and THW moved with a correlation of 0.70, which is strong. Recent behaviour matches the longer record: 0.71 over 1 year against 0.70 over 3. Over 5 years the correlation is 0.69, and the annualized covariance of weekly returns is 308.8 %².
By 3-year correlation, THW places #9 of the 168 assets tracked against IBB. The last year tells two different stories: IBB led by 21.7 percentage points, +55.4% for IBB against +33.7% for THW.
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 THW: side by side
| IBB (iShares Biotechnology ETF) | THW (abrdn World Healthcare Fund Shares of Beneficial Interest) | |
|---|---|---|
| 1-year return | +55.4% | +33.7% |
| 5-year return | +26.6% | +40.2% |
| Volatility (ann.) | 20.7% | 21.4% |
| Beta vs S&P 500 | 0.81 | 0.75 |
| Max drawdown (3Y) | -24.9% | -25.4% |
| Market cap | – | $0.6B |
| P/E (trailing) | – | 6.6 |
| Dividend yield | 0.22% | 0.00% |
| Expense ratio | 0.44% | – |
| Assets under management | $9.2B | – |
| Sector / category | ETF · Thematic | US Listed |
IBB is a Health fund from iShares: $9.2B under management, 235 holdings, a 0.44% expense ratio, a 0.22% trailing dividend yield.
Year-by-year returns
| Year | IBB | THW |
|---|---|---|
| 2022 | -13.7% | -1.2% |
| 2023 | +3.8% | -11.5% |
| 2024 | -2.4% | +5.4% |
| 2025 | +28.0% | +31.1% |
| 2026 | +27.4% | +18.0% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBB and THW good diversifiers for each other?
Only partially. A correlation of 0.70 means IBB and THW share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
FAQ
What is the correlation between IBB and THW?
Using weekly returns as of 2026-08-27: 0.70 over 3 years, with 0.71 over the last year and 0.69 over 5 years.
Is THW a good diversifier for IBB?
Only partially. A correlation of 0.70 means IBB and THW share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.70 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: IBB correlations · THW correlations
