IBB vs XLB: Correlation & Overlap
Measured on weekly returns over the past three years, iShares Biotechnology ETF (IBB) and Materials Select Sector SPDR Fund (XLB) carry a correlation of 0.58, a moderate link. The two funds also share 0% of their portfolios by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and XLB?
On 3 years of weekly data the IBB/XLB correlation comes out at 0.58, moderate. The past 12 months show a weaker link (0.44) than the 3-year average (0.58). The 5-year figure is 0.56, and annualized covariance runs at 202.6 %².
Among the 168 assets we track against IBB, XLB ranks #49 by 3-year correlation. The last year tells two different stories: IBB led by 37.8 percentage points, +55.4% for IBB against +17.6% for XLB. On a rolling one-year basis the correlation drifted between 0.42 and 0.74, a moderate band.
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 XLB: side by side
| IBB (iShares Biotechnology ETF) | XLB (Materials Select Sector SPDR Fund) | |
|---|---|---|
| 1-year return | +55.4% | +17.6% |
| 5-year return | +26.6% | +36.9% |
| Volatility (ann.) | 20.7% | 16.7% |
| Beta vs S&P 500 | 0.81 | 0.72 |
| Max drawdown (3Y) | -24.9% | -23.2% |
| Dividend yield | 0.22% | 1.68% |
| Expense ratio | 0.44% | 0.08% |
| Assets under management | $9.2B | $8.3B |
| Sector / category | ETF · Thematic | Sector ETF |
IBB, iShares's Health fund, carries $9.2B under management, 235 holdings, a 0.44% expense ratio, a 0.22% trailing dividend yield. XLB is a Natural Resources fund from State Street Investment Management: $8.3B under management, 26 holdings, a 0.08% expense ratio, a 1.68% trailing dividend yield.
Portfolio overlap between IBB and XLB
The two portfolios are largely distinct. Weighing the shared positions, 0% of the two funds is identical, spread across 0 common holdings. That shared book is a large part of why the returns line up.
Largest positions held only by IBB: AMGN (8.43%), VRTX (7.89%), GILD (7.10%), REGN (5.68%), MRNA (3.76%). Only by XLB: LIN (12.94%), NEM (8.02%), FCX (6.48%), SHW (4.87%), ECL (4.80%).
Overlap = sum of the smaller of the two weights across common holdings, from issuer disclosures as of 2026-08-26.
Year-by-year returns
| Year | IBB | XLB |
|---|---|---|
| 2022 | -13.7% | -12.3% |
| 2023 | +3.8% | +12.5% |
| 2024 | -2.4% | +0.1% |
| 2025 | +28.0% | +9.9% |
| 2026 | +27.4% | +18.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBB and XLB good diversifiers for each other?
Somewhat, no more. With 0.58 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between IBB and XLB?
Using weekly returns as of 2026-08-27: 0.58 over 3 years, with 0.44 over the last year and 0.56 over 5 years.
Is XLB a good diversifier for IBB?
Somewhat, no more. With 0.58 correlation, most large moves hit both names, and the diversification benefit stays modest.
How much do IBB and XLB overlap?
0% by weight, across 0 common holdings, based on issuer-disclosed portfolios as of 2026-08-26.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/ibb-vs-xlb.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/ibb-vs-xlb/)
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Related comparisons
Hubs: IBB correlations · XLB correlations
