IBB vs XLK: Correlation & Overlap
How closely do iShares Biotechnology ETF (IBB) and Technology Select Sector SPDR Fund (XLK) trade together? Their weekly returns over three years give a correlation of 0.42, which is moderate. By holdings, the two funds overlap 0% by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IBB and XLK?
Over the past 3 years, IBB and XLK moved with a correlation of 0.42, which is moderate. The link has loosened recently: the 1-year correlation (0.20) runs below the 3-year figure (0.42). Over 5 years the correlation is 0.50, and the annualized covariance of weekly returns is 208.8 %².
Among the 168 assets we track against IBB, XLK ranks #139 by 3-year correlation. On 12-month performance IBB holds a 12.0-point edge, +55.4% against +43.4%. This link changes with the market regime, having swung between 0.17 and 0.67 on a rolling one-year basis.
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 XLK: side by side
| IBB (iShares Biotechnology ETF) | XLK (Technology Select Sector SPDR Fund) | |
|---|---|---|
| 1-year return | +55.4% | +43.4% |
| 5-year return | +26.6% | +145.2% |
| Volatility (ann.) | 20.7% | 24.0% |
| Beta vs S&P 500 | 0.81 | 1.50 |
| Max drawdown (3Y) | -24.9% | -25.7% |
| Dividend yield | 0.22% | 0.45% |
| Expense ratio | 0.44% | 0.08% |
| Assets under management | $9.2B | $115.4B |
| 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. On the fund side, XLK sits in the Technology category at State Street Investment Management, with $115.4B under management, 73 holdings, a 0.08% expense ratio, a 0.45% trailing dividend yield.
Portfolio overlap between IBB and XLK
The two portfolios are largely distinct, with 0 holdings in common adding up to 0% of fund weight. Where correlation shows the co-movement, the overlap shows its source.
Largest positions held only by IBB: AMGN (8.43%), VRTX (7.89%), GILD (7.10%), REGN (5.68%), MRNA (3.76%). Only by XLK: NVDA (13.91%), AAPL (12.61%), MSFT (10.10%), AVGO (4.61%), AMD (4.09%).
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 | XLK |
|---|---|---|
| 2022 | -13.7% | -27.7% |
| 2023 | +3.8% | +56.0% |
| 2024 | -2.4% | +21.6% |
| 2025 | +28.0% | +24.6% |
| 2026 | +27.4% | +31.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IBB and XLK good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.42 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between IBB and XLK?
Using weekly returns as of 2026-08-27: 0.42 over 3 years, with 0.20 over the last year and 0.50 over 5 years.
Is XLK a good diversifier for IBB?
Yes, to a useful degree: a correlation of 0.42 leaves real independence between the two, which historically damped combined volatility.
How much do IBB and XLK overlap?
The two funds share 0 holdings amounting to 0% of weight, per issuer portfolio files dated 2026-08-26.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/ibb-vs-xlk.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/ibb-vs-xlk/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: IBB correlations · XLK correlations
