IWM vs NPO: Correlation
Measured on weekly returns over the past three years, iShares Russell 2000 ETF (IWM) and Enpro Inc. (NPO) carry a correlation of 0.69, a strong link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IWM and NPO?
Over the past 3 years, IWM and NPO moved with a correlation of 0.69, which is strong. The past 12 months show a weaker link (0.53) than the 3-year average (0.69). Over 5 years the correlation is 0.68, and the annualized covariance of weekly returns is 472.0 %².
Within IWM's tracked universe of 320 assets, NPO comes in at #47 by 3-year correlation. The trailing year gives NPO the advantage: +28.4% versus +37.1%, a 8.7-point spread. Note the risk asymmetry: NPO runs 1.7 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.
IWM vs NPO: side by side
| IWM (iShares Russell 2000 ETF) | NPO (Enpro Inc.) | |
|---|---|---|
| 1-year return | +28.4% | +37.1% |
| 5-year return | +41.5% | +270.5% |
| Volatility (ann.) | 19.8% | 34.4% |
| Beta vs S&P 500 | 1.06 | 1.27 |
| Max drawdown (3Y) | -27.5% | -33.7% |
| Market cap | – | $6.5B |
| P/E (trailing) | – | 149.1 |
| Dividend yield | 0.91% | 0.41% |
| Expense ratio | 0.19% | – |
| Assets under management | $80.1B | – |
| Sector / category | ETF · US Small & Mid Cap | US Listed |
On the fund side, IWM sits in the Small Blend category at iShares, with $80.1B under management, 1757 holdings, a 0.19% expense ratio, a 0.91% trailing dividend yield.
Year-by-year returns
| Year | IWM | NPO |
|---|---|---|
| 2022 | -20.5% | -0.2% |
| 2023 | +16.8% | +45.6% |
| 2024 | +11.4% | +10.9% |
| 2025 | +12.7% | +25.0% |
| 2026 | +22.3% | +44.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
NPO represents 0.21% of IWM's portfolio, so part of any move in IWM is NPO itself, and the correlation between them is partly mechanical.
Are IWM and NPO good diversifiers for each other?
Somewhat, no more. With 0.69 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between IWM and NPO?
As of 2026-08-27, the correlation of weekly returns between IWM and NPO is 0.69 over 3 years, 0.53 over 1 year and 0.68 over 5 years.
Is NPO a good diversifier for IWM?
Somewhat, no more. With 0.69 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.69 mean?
On the −1 to +1 scale, 0.69 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/iwm-vs-npo.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/iwm-vs-npo/)
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Related comparisons
Hubs: IWM correlations · NPO correlations
