AEE vs ATO: Correlation
Measured on weekly returns over the past three years, Ameren (AEE) and Atmos Energy (ATO) carry a correlation of 0.73, a strong link.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are AEE and ATO?
Across a 3-year window, the weekly returns of AEE and ATO correlate at 0.73, strong. Little has changed lately, as the 1-year reading of 0.80 lands near the 3-year figure. Stretching to 5 years gives 0.79, with an annualized covariance of 206.7 %².
By 3-year correlation, ATO places #16 of the 35 assets tracked against AEE. The trailing year gives AEE the advantage: +8.8% versus +2.9%, a 5.9-point spread. On a rolling one-year basis the correlation drifted between 0.60 and 0.86, 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.
AEE vs ATO: side by side
| AEE (Ameren) | ATO (Atmos Energy) | |
|---|---|---|
| 1-year return | +8.8% | +2.9% |
| 5-year return | +39.7% | +94.1% |
| Volatility (ann.) | 17.8% | 15.9% |
| Beta vs S&P 500 | 0.10 | 0.15 |
| Max drawdown (3Y) | -16.5% | -12.7% |
| Market cap | $29.6B | $28.3B |
| P/E (trailing) | 19.0 | 19.9 |
| Dividend yield | 2.71% | 2.28% |
| Sector / category | Utilities | Utilities |
Year-by-year returns
| Year | AEE | ATO |
|---|---|---|
| 2022 | +2.5% | +9.6% |
| 2023 | -16.1% | +6.2% |
| 2024 | +27.5% | +23.4% |
| 2025 | +15.3% | +23.1% |
| 2026 | +8.4% | +1.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are AEE and ATO 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 AEE and ATO?
The AEE/ATO correlation stands at 0.73 on a 3-year window (1 year: 0.80, 5 years: 0.79), computed from weekly returns as of 2026-08-27.
Is ATO a good diversifier for AEE?
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.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/aee-vs-ato.json
Embed this badge (it refreshes with the data), with attribution:
[](https://www.pairbook.io/pair/aee-vs-ato/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: AEE correlations · ATO correlations
