COST vs SUNE: Correlation
How closely do Costco (COST) and SUNation Energy, Inc. (SUNE) trade together? Their weekly returns over three years give a correlation of -0.21, which is negative.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are COST and SUNE?
On 3 years of weekly data the COST/SUNE correlation comes out at -0.21, negative, meaning they tend to move in opposite directions. The link has tightened recently: the 1-year correlation (-0.07) runs above the 3-year figure (-0.21). The 5-year figure is -0.12, and annualized covariance runs at -801.8 %².
Among the 33 assets we track against COST, SUNE ranks #27 by 3-year correlation. The last year tells two different stories: SUNE led by 47.7 percentage points, -1.0% for COST against +46.7% for SUNE. Risk is not evenly split, since SUNE carries 9.6 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.
COST vs SUNE: side by side
| COST (Costco) | SUNE (SUNation Energy, Inc.) | |
|---|---|---|
| 1-year return | -1.0% | +46.7% |
| 5-year return | +116.3% | -100.0% |
| Volatility (ann.) | 19.8% | 189.9% |
| Beta vs S&P 500 | 0.45 | -0.81 |
| Max drawdown (3Y) | -20.7% | -100.0% |
| Market cap | $414.5B | – |
| P/E (trailing) | 48.1 | 1.1 |
| Dividend yield | 0.56% | 0.00% |
| Sector / category | Consumer Staples | US Listed |
Year-by-year returns
| Year | COST | SUNE |
|---|---|---|
| 2022 | -19.0% | -75.7% |
| 2023 | +49.0% | -74.7% |
| 2024 | +39.6% | -99.4% |
| 2025 | -5.4% | -99.8% |
| 2026 | +8.9% | +113.6% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are COST and SUNE good diversifiers for each other?
Yes: at -0.21, the two have gone their own ways historically, which is what genuine diversification looks like.
FAQ
What is the correlation between COST and SUNE?
As of 2026-08-27, the correlation of weekly returns between COST and SUNE is -0.21 over 3 years, -0.07 over 1 year and -0.12 over 5 years.
Is SUNE a good diversifier for COST?
Yes: at -0.21, the two have gone their own ways historically, which is what genuine diversification looks like.
What does a correlation of -0.21 mean?
On the −1 to +1 scale, -0.21 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/cost-vs-sune.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/cost-vs-sune/)
Free with attribution; caching and terms are described in the API documentation.
Related comparisons
Hubs: COST correlations · SUNE correlations
