IBB vs RSP: Correlation & Overlap
Measured on weekly returns over the past three years, iShares Biotechnology ETF (IBB) and Invesco S&P 500 Equal Weight ETF (RSP) carry a correlation of 0.66, a strong link. The two funds also share 2.6% of their portfolios by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and RSP?
Over the past 3 years, IBB and RSP moved with a correlation of 0.66, which is strong. The link has loosened recently: the 1-year correlation (0.48) runs below the 3-year figure (0.66). Over 5 years the correlation is 0.65, and the annualized covariance of weekly returns is 179.5 %².
Among the 168 assets we track against IBB, RSP ranks #13 by 3-year correlation. Their recent paths diverged sharply: over the last 12 months IBB outperformed by 36.2 percentage points (+55.4% for IBB against +19.2% for RSP). Across three years, the rolling one-year figure varied moderately, from 0.53 to 0.82. Note the risk asymmetry: IBB runs 1.6 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.
IBB vs RSP: side by side
| IBB (iShares Biotechnology ETF) | RSP (Invesco S&P 500 Equal Weight ETF) | |
|---|---|---|
| 1-year return | +55.4% | +19.2% |
| 5-year return | +26.6% | +53.9% |
| Volatility (ann.) | 20.7% | 13.2% |
| Beta vs S&P 500 | 0.81 | 0.77 |
| Max drawdown (3Y) | -24.9% | -17.8% |
| Dividend yield | 0.22% | 1.49% |
| Expense ratio | 0.44% | 0.20% |
| Assets under management | $9.2B | $97.3B |
| Sector / category | ETF · Thematic | ETF · US Large Cap |
IBB is a Health fund from iShares: $9.2B under management, 235 holdings, a 0.44% expense ratio, a 0.22% trailing dividend yield. On the fund side, RSP sits in the Large Blend category at Invesco, with $97.3B under management, 505 holdings, a 0.20% expense ratio, a 1.49% trailing dividend yield.
Portfolio overlap between IBB and RSP
The two portfolios are largely distinct. Weighing the shared positions, 2.6% of the two funds is identical, spread across 9 common holdings. That shared book is a large part of why the returns line up.
| Common holding | Weight in IBB | Weight in RSP |
|---|---|---|
| MRNA | 3.76% | 0.61% |
| CRL | 0.97% | 0.29% |
| TECH | 0.78% | 0.26% |
| REGN | 5.68% | 0.25% |
| AMGN | 8.43% | 0.24% |
| VRTX | 7.89% | 0.23% |
| GILD | 7.10% | 0.23% |
| INCY | 1.75% | 0.23% |
| BIIB | 2.23% | 0.21% |
Largest positions held only by IBB: ARGX (3.76%), NTRA (3.19%), RVMD (2.83%), ILMN (2.34%), ALNY (2.19%). Only by RSP: ZBRA (0.31%), DASH (0.29%), EXPE (0.28%), PYPL (0.28%), VEEV (0.28%).
Overlap = sum of the smaller of the two weights across common holdings, from issuer disclosures as of 2026-08-26. Top 9 common positions shown.
Year-by-year returns
| Year | IBB | RSP |
|---|---|---|
| 2022 | -13.7% | -11.6% |
| 2023 | +3.8% | +13.7% |
| 2024 | -2.4% | +12.8% |
| 2025 | +28.0% | +11.2% |
| 2026 | +27.4% | +16.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBB and RSP good diversifiers for each other?
To a limited degree. At 0.66 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
FAQ
What is the correlation between IBB and RSP?
Using weekly returns as of 2026-08-27: 0.66 over 3 years, with 0.48 over the last year and 0.65 over 5 years.
Is RSP a good diversifier for IBB?
To a limited degree. At 0.66 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
How much do IBB and RSP overlap?
Per the issuers' own portfolio disclosures (2026-08-26), the overlap is 2.6% by weight over 9 common positions.
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Related comparisons
Hubs: IBB correlations · RSP correlations
