PNW vs SO: Correlation
How closely do Pinnacle West Capital (PNW) and Southern Company (SO) trade together? Their weekly returns over three years give a correlation of 0.73, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are PNW and SO?
Across a 3-year window, the weekly returns of PNW and SO correlate at 0.73, strong. Little has changed lately, as the 1-year reading of 0.77 lands near the 3-year figure. Stretching to 5 years gives 0.74, with an annualized covariance of 219.2 %².
By 3-year correlation, SO places #11 of the 36 assets tracked against PNW. The trailing year gives PNW the advantage: +12.4% versus -1.4%, a 13.8-point spread. On a rolling one-year basis the correlation drifted between 0.55 and 0.80, a moderate band.
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.
PNW vs SO: side by side
| PNW (Pinnacle West Capital) | SO (Southern Company) | |
|---|---|---|
| 1-year return | +12.4% | -1.4% |
| 5-year return | +59.3% | +62.6% |
| Volatility (ann.) | 18.2% | 16.5% |
| Beta vs S&P 500 | 0.09 | -0.02 |
| Max drawdown (3Y) | -14.4% | -15.0% |
| Market cap | $11.9B | $102.4B |
| P/E (trailing) | 18.8 | 21.7 |
| Dividend yield | 3.67% | 3.32% |
| Sector / category | Utilities | Utilities |
Year-by-year returns
| Year | PNW | SO |
|---|---|---|
| 2022 | +13.0% | +8.2% |
| 2023 | -1.2% | +2.2% |
| 2024 | +23.5% | +21.7% |
| 2025 | +8.9% | +9.5% |
| 2026 | +13.5% | +4.6% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are PNW and SO good diversifiers for each other?
Somewhat, no more. With 0.73 correlation, most large moves hit both names, and the diversification benefit stays modest.
FAQ
What is the correlation between PNW and SO?
As of 2026-08-27, the correlation of weekly returns between PNW and SO is 0.73 over 3 years, 0.77 over 1 year and 0.74 over 5 years.
Is SO a good diversifier for PNW?
Somewhat, no more. With 0.73 correlation, most large moves hit both names, and the diversification benefit stays modest.
What does a correlation of 0.73 mean?
On the −1 to +1 scale, 0.73 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.
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Related comparisons
Hubs: PNW correlations · SO correlations
