RMBS vs XLK: Correlation
How closely do Rambus, Inc. (RMBS) and Technology Select Sector SPDR Fund (XLK) trade together? Their weekly returns over three years give a correlation of 0.62, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are RMBS and XLK?
On 3 years of weekly data the RMBS/XLK correlation comes out at 0.62, strong. Little has changed lately, as the 1-year reading of 0.57 lands near the 3-year figure. The 5-year figure is 0.60, and annualized covariance runs at 884.6 %².
Within RMBS's tracked universe of 12 assets, XLK comes in at #4 by 3-year correlation. The last year tells two different stories: XLK led by 22.0 percentage points, +21.4% for RMBS against +43.4% for XLK. Note the risk asymmetry: RMBS runs 2.5 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.
RMBS vs XLK: side by side
| RMBS (Rambus, Inc.) | XLK (Technology Select Sector SPDR Fund) | |
|---|---|---|
| 1-year return | +21.4% | +43.4% |
| 5-year return | +269.6% | +145.2% |
| Volatility (ann.) | 59.1% | 24.0% |
| Beta vs S&P 500 | 2.22 | 1.50 |
| Max drawdown (3Y) | -51.5% | -25.7% |
| Market cap | $9.9B | – |
| P/E (trailing) | 41.4 | – |
| Dividend yield | 0.00% | 0.45% |
| Expense ratio | – | 0.08% |
| Assets under management | – | $115.4B |
| Sector / category | US Listed | Sector ETF |
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.
Year-by-year returns
| Year | RMBS | XLK |
|---|---|---|
| 2022 | +21.9% | -27.7% |
| 2023 | +90.5% | +56.0% |
| 2024 | -22.5% | +21.6% |
| 2025 | +73.8% | +24.6% |
| 2026 | -0.8% | +31.3% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are RMBS and XLK good diversifiers for each other?
Only partially. A correlation of 0.62 means RMBS and XLK 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 RMBS and XLK?
Using weekly returns as of 2026-08-27: 0.62 over 3 years, with 0.57 over the last year and 0.60 over 5 years.
Is XLK a good diversifier for RMBS?
Only partially. A correlation of 0.62 means RMBS and XLK share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.62 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.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/rmbs-vs-xlk.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/rmbs-vs-xlk/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: RMBS correlations · XLK correlations
