AJG vs AON: Correlation
How closely do Arthur J. Gallagher & Co. (AJG) and Aon plc (AON) trade together? Their weekly returns over three years give a correlation of 0.67, which is strong.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are AJG and AON?
On 3 years of weekly data the AJG/AON correlation comes out at 0.67, strong. The relationship has been stable: the 1-year correlation (0.72) sits close to the 3-year figure. The 5-year figure is 0.71, and annualized covariance runs at 361.5 %².
AON is one of the assets that tracks AJG most closely: it ranks #3 out of the 32 assets we track against AJG. Over the last 12 months AON came out ahead by 7.3 percentage points (-11.9% against -4.6%). The rolling one-year correlation stayed in a tight band between 0.55 and 0.79 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.
AJG vs AON: side by side
| AJG (Arthur J. Gallagher & Co.) | AON (Aon plc) | |
|---|---|---|
| 1-year return | -11.9% | -4.6% |
| 5-year return | +91.1% | +27.0% |
| Volatility (ann.) | 25.0% | 21.7% |
| Beta vs S&P 500 | 0.36 | 0.34 |
| Max drawdown (3Y) | -44.4% | -24.2% |
| Market cap | $66.7B | $74.2B |
| P/E (trailing) | 43.1 | 19.5 |
| Dividend yield | 1.02% | 0.86% |
| Sector / category | Financials | Financials |
Year-by-year returns
| Year | AJG | AON |
|---|---|---|
| 2022 | +12.4% | +0.6% |
| 2023 | +20.5% | -2.3% |
| 2024 | +27.3% | +24.5% |
| 2025 | -8.0% | -1.2% |
| 2026 | +1.2% | -0.5% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are AJG and AON good diversifiers for each other?
To a limited degree. At 0.67 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
FAQ
What is the correlation between AJG and AON?
Using weekly returns as of 2026-08-27: 0.67 over 3 years, with 0.72 over the last year and 0.71 over 5 years.
Is AON a good diversifier for AJG?
To a limited degree. At 0.67 the two still catch most of the same waves, so the pair smooths returns a little without insulating either from a shared selloff.
What does a correlation of 0.67 mean?
A reading of 0.67 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/ajg-vs-aon.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/ajg-vs-aon/)
The core API is free. Terms and every endpoint in the API documentation.
Related comparisons
Hubs: AJG correlations · AON correlations
