IWM vs PLSE: Correlation
iShares Russell 2000 ETF (IWM) and Pulse Biosciences, Inc (PLSE) show a moderate relationship: their 3-year correlation of weekly returns is 0.40.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are IWM and PLSE?
Across a 3-year window, the weekly returns of IWM and PLSE correlate at 0.40, moderate. Lately the two have drifted apart, with the 1-year correlation at 0.22 versus 0.40 over 3 years. Stretching to 5 years gives 0.29, with an annualized covariance of 685.6 %².
Within IWM's tracked universe of 320 assets, PLSE comes in at #299 by 3-year correlation. The last year tells two different stories: PLSE led by 178.0 percentage points, +28.4% for IWM against +206.4% for PLSE. Note the risk asymmetry: PLSE runs 4.4 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 PLSE: side by side
| IWM (iShares Russell 2000 ETF) | PLSE (Pulse Biosciences, Inc) | |
|---|---|---|
| 1-year return | +28.4% | +206.4% |
| 5-year return | +41.5% | +82.4% |
| Volatility (ann.) | 19.8% | 86.6% |
| Beta vs S&P 500 | 1.06 | 1.55 |
| Max drawdown (3Y) | -27.5% | -48.5% |
| Market cap | – | $3.5B |
| 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 |
IWM, iShares's Small Blend fund, carries $80.1B under management, 1757 holdings, a 0.19% expense ratio, a 0.91% trailing dividend yield.
Year-by-year returns
| Year | IWM | PLSE |
|---|---|---|
| 2022 | -20.5% | -81.3% |
| 2023 | +16.8% | +341.9% |
| 2024 | +11.4% | +42.2% |
| 2025 | +12.7% | -21.1% |
| 2026 | +22.3% | +253.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are IWM and PLSE good diversifiers for each other?
Reasonably. At 0.40, IWM and PLSE keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between IWM and PLSE?
Using weekly returns as of 2026-08-27: 0.40 over 3 years, with 0.22 over the last year and 0.29 over 5 years.
Is PLSE a good diversifier for IWM?
Reasonably. At 0.40, IWM and PLSE keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.40 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/iwm-vs-plse.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/iwm-vs-plse/)
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Related comparisons
Hubs: IWM correlations · PLSE correlations
