IWM vs ULBI: Correlation
iShares Russell 2000 ETF (IWM) and Ultralife Corporation (ULBI) show a moderate relationship: their 3-year correlation of weekly returns is 0.47.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IWM and ULBI?
Over the past 3 years, IWM and ULBI moved with a correlation of 0.47, which is moderate. Little has changed lately, as the 1-year reading of 0.46 lands near the 3-year figure. Over 5 years the correlation is 0.32, and the annualized covariance of weekly returns is 548.2 %².
Among the 320 assets we track against IWM, ULBI ranks #267 by 3-year correlation. The last year tells two different stories: IWM led by 34.1 percentage points, +28.4% for IWM against -5.7% for ULBI. Risk is not evenly split, since ULBI carries 3.0 times the volatility of the other side.
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 ULBI: side by side
| IWM (iShares Russell 2000 ETF) | ULBI (Ultralife Corporation) | |
|---|---|---|
| 1-year return | +28.4% | -5.7% |
| 5-year return | +41.5% | -19.1% |
| Volatility (ann.) | 19.8% | 59.1% |
| Beta vs S&P 500 | 1.06 | 1.74 |
| Max drawdown (3Y) | -27.5% | -68.8% |
| Market cap | – | $0.1B |
| P/E (trailing) | – | – |
| Dividend yield | 0.91% | 0.00% |
| 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 | ULBI |
|---|---|---|
| 2022 | -20.5% | -36.1% |
| 2023 | +16.8% | +76.7% |
| 2024 | +11.4% | +9.2% |
| 2025 | +12.7% | -23.2% |
| 2026 | +22.3% | +13.8% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IWM and ULBI good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.47 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between IWM and ULBI?
The IWM/ULBI correlation stands at 0.47 on a 3-year window (1 year: 0.46, 5 years: 0.32), computed from weekly returns as of 2026-08-27.
Is ULBI a good diversifier for IWM?
Yes, to a useful degree: a correlation of 0.47 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.47 mean?
On the −1 to +1 scale, 0.47 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-ulbi.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/iwm-vs-ulbi/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: IWM correlations · ULBI correlations
