CSTL vs QQQ: Correlation
How closely do Castle Biosciences, Inc. (CSTL) and Invesco QQQ Trust (QQQ) trade together? Their weekly returns over three years give a correlation of 0.11, which is weak.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CSTL and QQQ?
On 3 years of weekly data the CSTL/QQQ correlation comes out at 0.11, weak. The past 12 months show a weaker link (-0.12) than the 3-year average (0.11). The 5-year figure is 0.28, and annualized covariance runs at 134.3 %².
QQQ is close to the least connected end of CSTL's tracked universe, ranking #9 of 12. Their recent paths diverged sharply: over the last 12 months CSTL outperformed by 27.5 percentage points (+53.8% for CSTL against +26.3% for QQQ). Note the risk asymmetry: CSTL runs 3.3 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.
CSTL vs QQQ: side by side
| CSTL (Castle Biosciences, Inc.) | QQQ (Invesco QQQ Trust) | |
|---|---|---|
| 1-year return | +53.8% | +26.3% |
| 5-year return | -54.0% | +95.4% |
| Volatility (ann.) | 64.2% | 19.6% |
| Beta vs S&P 500 | 0.79 | 1.28 |
| Max drawdown (3Y) | -57.8% | -22.8% |
| Market cap | $1.0B | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 0.44% |
| Expense ratio | – | 0.18% |
| Assets under management | – | $452.8B |
| Sector / category | US Listed | ETF · US Growth & Tech |
QQQ is a Large Growth fund from Invesco: $452.8B under management, 104 holdings, a 0.18% expense ratio, a 0.44% trailing dividend yield.
Year-by-year returns
| Year | CSTL | QQQ |
|---|---|---|
| 2022 | -45.1% | -32.6% |
| 2023 | -8.3% | +54.9% |
| 2024 | +23.5% | +25.6% |
| 2025 | +46.0% | +20.8% |
| 2026 | -11.9% | +17.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CSTL and QQQ good diversifiers for each other?
Yes: at 0.11, the two have gone their own ways historically, which is what genuine diversification looks like.
FAQ
What is the correlation between CSTL and QQQ?
Using weekly returns as of 2026-08-27: 0.11 over 3 years, with -0.12 over the last year and 0.28 over 5 years.
Is QQQ a good diversifier for CSTL?
Yes: at 0.11, the two have gone their own ways historically, which is what genuine diversification looks like.
What does a correlation of 0.11 mean?
A reading of 0.11 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/cstl-vs-qqq.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/cstl-vs-qqq/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: CSTL correlations · QQQ correlations
