SO vs XLU: Correlation
Measured on weekly returns over the past three years, Southern Company (SO) and Utilities Select Sector SPDR Fund (XLU) carry a correlation of 0.79, a strong link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are SO and XLU?
Over the past 3 years, SO and XLU moved with a correlation of 0.79, which is strong. The relationship has been stable: the 1-year correlation (0.84) sits close to the 3-year figure. Over 5 years the correlation is 0.84, and the annualized covariance of weekly returns is 207.2 %².
Among the 48 assets we track against SO, XLU ranks #5 by 3-year correlation. On 12-month performance XLU holds a 5.5-point edge, -1.4% against +4.1%. On a rolling one-year basis the correlation drifted between 0.52 and 0.91, 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.
SO vs XLU: side by side
| SO (Southern Company) | XLU (Utilities Select Sector SPDR Fund) | |
|---|---|---|
| 1-year return | -1.4% | +4.1% |
| 5-year return | +62.6% | +46.3% |
| Volatility (ann.) | 16.5% | 15.8% |
| Beta vs S&P 500 | -0.02 | 0.26 |
| Max drawdown (3Y) | -15.0% | -13.1% |
| Market cap | $102.4B | – |
| P/E (trailing) | 21.7 | – |
| Dividend yield | 3.32% | 2.70% |
| Expense ratio | – | 0.08% |
| Assets under management | – | $23.1B |
| Sector / category | Utilities | Sector ETF |
XLU is an Utilities fund from State Street Investment Management: $23.1B under management, 31 holdings, a 0.08% expense ratio, a 2.70% trailing dividend yield.
Year-by-year returns
| Year | SO | XLU |
|---|---|---|
| 2022 | +8.2% | +1.4% |
| 2023 | +2.2% | -7.2% |
| 2024 | +21.7% | +23.3% |
| 2025 | +9.5% | +16.0% |
| 2026 | +4.6% | +2.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Fund exposure
SO represents 7.45% of XLU's portfolio, so part of any move in XLU is SO itself, and the correlation between them is partly mechanical.
Are SO and XLU good diversifiers for each other?
Only partially. A correlation of 0.79 means SO and XLU share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
FAQ
What is the correlation between SO and XLU?
Using weekly returns as of 2026-08-27: 0.79 over 3 years, with 0.84 over the last year and 0.84 over 5 years.
Is XLU a good diversifier for SO?
Only partially. A correlation of 0.79 means SO and XLU share most of their swings. Pairing them dampens volatility somewhat, but it will not protect against a common drawdown.
What does a correlation of 0.79 mean?
A reading of 0.79 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/so-vs-xlu.json
Drop this badge in a README or notebook; it updates with the data:
[](https://www.pairbook.io/pair/so-vs-xlu/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: SO correlations · XLU correlations
