ERII vs VXZ: Correlation
How closely do Energy Recovery, Inc. (ERII) and iPath Series B S&P 500 VIX Mid-Term Futures ETN (VXZ) trade together? Their weekly returns over three years give a correlation of -0.33, which is negative.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are ERII and VXZ?
Across a 3-year window, the weekly returns of ERII and VXZ correlate at -0.33, negative, meaning they tend to move in opposite directions. Little has changed lately, as the 1-year reading of -0.28 lands near the 3-year figure. Stretching to 5 years gives -0.35, with an annualized covariance of -433.1 %².
Among the 11 assets we track against ERII, VXZ sits near the bottom by co-movement, at rank #11. The last year tells two different stories: VXZ led by 29.7 percentage points, -45.8% for ERII against -16.1% for VXZ. Note the risk asymmetry: ERII runs 2.0 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.
ERII vs VXZ: side by side
| ERII (Energy Recovery, Inc.) | VXZ (iPath Series B S&P 500 VIX Mid-Term Futures ETN) | |
|---|---|---|
| 1-year return | -45.8% | -16.1% |
| 5-year return | -60.7% | -53.1% |
| Volatility (ann.) | 51.2% | 25.6% |
| Beta vs S&P 500 | 1.44 | -1.31 |
| Max drawdown (3Y) | -72.4% | -36.4% |
| Market cap | $0.4B | – |
| P/E (trailing) | 30.4 | – |
| Dividend yield | 0.00% | – |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | ERII | VXZ |
|---|---|---|
| 2022 | -4.7% | +0.5% |
| 2023 | -8.1% | -44.0% |
| 2024 | -22.0% | -12.7% |
| 2025 | -8.2% | +5.7% |
| 2026 | -41.4% | -10.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are ERII and VXZ good diversifiers for each other?
Yes. With a correlation of -0.33, ERII and VXZ have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
FAQ
What is the correlation between ERII and VXZ?
As of 2026-08-27, the correlation of weekly returns between ERII and VXZ is -0.33 over 3 years, -0.28 over 1 year and -0.35 over 5 years.
Is VXZ a good diversifier for ERII?
Yes. With a correlation of -0.33, ERII and VXZ have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
What does a correlation of -0.33 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/erii-vs-vxz.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/erii-vs-vxz/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: ERII correlations · VXZ correlations
