DUK vs SO: Correlation
How closely do Duke Energy (DUK) and Southern Company (SO) trade together? Their weekly returns over three years give a correlation of 0.85, which is very strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are DUK and SO?
Over the past 3 years, DUK and SO moved with a correlation of 0.85, which is very strong, meaning they move nearly in lockstep. Little has changed lately, as the 1-year reading of 0.91 lands near the 3-year figure. Over 5 years the correlation is 0.87, and the annualized covariance of weekly returns is 224.5 %².
In DUK's tracked universe of 53 assets, SO sits right near the top at #1. Twelve-month performance is nearly a tie, at +1.1% for DUK and -1.4% for SO. The rolling one-year correlation stayed in a tight band between 0.72 and 0.90 over the past three years, which points to a structural rather than episodic relationship.
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.
DUK vs SO: side by side
| DUK (Duke Energy) | SO (Southern Company) | |
|---|---|---|
| 1-year return | +1.1% | -1.4% |
| 5-year return | +39.8% | +62.6% |
| Volatility (ann.) | 15.9% | 16.5% |
| Beta vs S&P 500 | -0.09 | -0.02 |
| Max drawdown (3Y) | -11.6% | -15.0% |
| Market cap | $94.2B | $102.4B |
| P/E (trailing) | 18.3 | 21.7 |
| Dividend yield | 3.49% | 3.32% |
| Sector / category | Utilities | Utilities |
Year-by-year returns
| Year | DUK | SO |
|---|---|---|
| 2022 | +2.0% | +8.2% |
| 2023 | -1.6% | +2.2% |
| 2024 | +15.6% | +21.7% |
| 2025 | +12.7% | +9.5% |
| 2026 | +5.8% | +4.6% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are DUK and SO good diversifiers for each other?
No: a correlation of 0.85 means DUK and SO tend to fall together, which is precisely when diversification is supposed to help.
FAQ
What is the correlation between DUK and SO?
The DUK/SO correlation stands at 0.85 on a 3-year window (1 year: 0.91, 5 years: 0.87), computed from weekly returns as of 2026-08-27.
Is SO a good diversifier for DUK?
No: a correlation of 0.85 means DUK and SO tend to fall together, which is precisely when diversification is supposed to help.
What does a correlation of 0.85 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.
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Related comparisons
Hubs: DUK correlations · SO correlations
