CWT vs TGEN: Correlation
How closely do California Water Service Group (CWT) and Tecogen Inc. (TGEN) trade together? Their weekly returns over three years give a correlation of -0.26, which is negative.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are CWT and TGEN?
On 3 years of weekly data the CWT/TGEN correlation comes out at -0.26, negative, meaning they tend to move in opposite directions. Little has changed lately, as the 1-year reading of -0.27 lands near the 3-year figure. The 5-year figure is -0.13, and annualized covariance runs at -620.5 %².
Among the 15 assets we track against CWT, TGEN sits near the bottom by co-movement, at rank #12. The last year tells two different stories: CWT led by 69.1 percentage points, +9.3% for CWT against -59.8% for TGEN. One caveat on sizing: TGEN is 4.8 times as volatile as the other leg, so an equal-dollar split is far from equal-risk.
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.
CWT vs TGEN: side by side
| CWT (California Water Service Group) | TGEN (Tecogen Inc.) | |
|---|---|---|
| 1-year return | +9.3% | -59.8% |
| 5-year return | -12.2% | +76.1% |
| Volatility (ann.) | 22.3% | 106.2% |
| Beta vs S&P 500 | 0.10 | 1.92 |
| Max drawdown (3Y) | -24.1% | -83.4% |
| Market cap | $3.1B | $0.1B |
| P/E (trailing) | 22.6 | – |
| Dividend yield | 2.53% | 0.00% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | CWT | TGEN |
|---|---|---|
| 2022 | -14.1% | +4.2% |
| 2023 | -12.8% | -35.2% |
| 2024 | -10.6% | +80.9% |
| 2025 | -1.8% | +237.2% |
| 2026 | +18.2% | -35.8% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are CWT and TGEN good diversifiers for each other?
Yes: at -0.26, the two have gone their own ways historically, which is what genuine diversification looks like.
FAQ
What is the correlation between CWT and TGEN?
Using weekly returns as of 2026-08-27: -0.26 over 3 years, with -0.27 over the last year and -0.13 over 5 years.
Is TGEN a good diversifier for CWT?
Yes: at -0.26, the two have gone their own ways historically, which is what genuine diversification looks like.
What does a correlation of -0.26 mean?
On the −1 to +1 scale, -0.26 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/cwt-vs-tgen.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/cwt-vs-tgen/)
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Related comparisons
Hubs: CWT correlations · TGEN correlations
