Pair · Stocks & ETFs
Nasdaq-100 ETF vs Russell 2000 ETF
As of 22 Oct 2026, Nasdaq-100 ETF (QQQ) and Russell 2000 ETF (IWM) have a 120-day daily-return correlation of 0.73 — strong positive. Their prices passed the Engle–Granger cointegration test at the 5% level, so the ratio between them has tended to pull back toward its usual level.
Last updated 22 Oct 2026 · data through the 22 Oct 2026 UTC daily candle
The working detail for QQQ/IWM
- Hedge ratio and mean-reversion half-life
- Live spread z-score with a ±2σ band — how stretched the pair is today
- Rolling history of the relationship, and the days it breaks down
- Pass/fail gates and a composite score across every tracked pair
Common questions
Are Nasdaq-100 ETF and Russell 2000 ETF correlated?
As of 22 Oct 2026, the correlation between QQQ and IWM daily returns over the last 120 days is 0.73 (strong positive). Near 1 means they usually move the same way on the same day; near 0, independently; below 0, in opposite directions.
Are QQQ and IWM cointegrated?
Yes. As of 22 Oct 2026, their prices passed the Engle–Granger cointegration test at the 5% level over the last 120 days. The test is re-run every day on fresh prices, so the answer can change.
What’s the difference between correlation and cointegration?
Correlation measures whether two assets’ daily returns move together. Cointegration asks something stronger: whether the gap between their prices — their ratio — is tethered and tends to pull back toward its usual level. Two assets can be highly correlated yet drift apart for months; that is correlation without cointegration.