IBB vs VTI: Correlation & Overlap
iShares Biotechnology ETF (IBB) and Vanguard Total Stock Market ETF (VTI) show a moderate relationship: their 3-year correlation of weekly returns is 0.59. By holdings, the two funds overlap 1.8% by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and VTI?
Across a 3-year window, the weekly returns of IBB and VTI correlate at 0.59, moderate. The link has loosened recently: the 1-year correlation (0.39) runs below the 3-year figure (0.59). Stretching to 5 years gives 0.65, with an annualized covariance of 178.4 %².
Among the 168 assets we track against IBB, VTI ranks #41 by 3-year correlation. Correlation aside, the last 12 months split them widely, with IBB ahead by 34.7 points (+55.4% versus +20.7%). The rolling one-year correlation moved between 0.43 and 0.85 over the past three years, a moderate range.
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 VTI: side by side
| IBB (iShares Biotechnology ETF) | VTI (Vanguard Total Stock Market ETF) | |
|---|---|---|
| 1-year return | +55.4% | +20.7% |
| 5-year return | +26.6% | +74.8% |
| Volatility (ann.) | 20.7% | 14.6% |
| Beta vs S&P 500 | 0.81 | 1.01 |
| Max drawdown (3Y) | -24.9% | -19.3% |
| Dividend yield | 0.22% | 1.06% |
| Expense ratio | 0.44% | 0.03% |
| Assets under management | $9.2B | $2,290.0B |
| Sector / category | ETF · Thematic | ETF · US Large Cap |
IBB, iShares's Health fund, carries $9.2B under management, 235 holdings, a 0.44% expense ratio, a 0.22% trailing dividend yield. VTI, Vanguard's Large Blend fund, carries $2,290.0B under management, 3140 holdings, a 0.03% expense ratio, a 1.06% trailing dividend yield.
Portfolio overlap between IBB and VTI
The two portfolios are largely distinct: 1.8% of the funds' weight sits in the same underlying holdings (197 common positions). Correlation tells you they move together; overlap tells you why.
| Common holding | Weight in IBB | Weight in VTI |
|---|---|---|
| AMGN | 8.43% | 0.29% |
| GILD | 7.10% | 0.23% |
| VRTX | 7.89% | 0.17% |
| REGN | 5.68% | 0.11% |
| RVMD | 2.83% | 0.05% |
| NTRA | 3.19% | 0.05% |
| BIIB | 2.23% | 0.04% |
| ILMN | 2.34% | 0.04% |
| ALNY | 2.19% | 0.04% |
| UTHR | 1.46% | 0.03% |
| INSM | 1.84% | 0.03% |
| INCY | 1.75% | 0.03% |
| MRNA | 3.76% | 0.03% |
| ROIV | 1.31% | 0.02% |
| NBIX | 1.07% | 0.02% |
Largest positions held only by IBB: ARGX (3.76%), ONC (2.07%), GMAB (1.22%), ASND (1.07%), BNTX (0.71%). Only by VTI: NVDA (6.42%), AAPL (6.31%), MSFT (4.80%), AMZN (3.66%), GOOGL (2.91%).
Overlap = sum of the smaller of the two weights across common holdings, from issuer disclosures as of 2026-08-26. Top 15 common positions shown.
Year-by-year returns
| Year | IBB | VTI |
|---|---|---|
| 2022 | -13.7% | -19.5% |
| 2023 | +3.8% | +26.0% |
| 2024 | -2.4% | +23.8% |
| 2025 | +28.0% | +17.1% |
| 2026 | +27.4% | +14.2% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBB and VTI good diversifiers for each other?
To a limited degree. At 0.59 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 VTI?
The IBB/VTI correlation stands at 0.59 on a 3-year window (1 year: 0.39, 5 years: 0.65), computed from weekly returns as of 2026-08-27.
Is VTI a good diversifier for IBB?
To a limited degree. At 0.59 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 VTI overlap?
The two funds share 197 holdings amounting to 1.8% of weight, per issuer portfolio files dated 2026-08-26.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/ibb-vs-vti.json
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Hubs: IBB correlations · VTI correlations
