One of the best investments we can make is in our own knowledge and skill set. With that in mind, this article will work through how we can use Return On Equity (ROE) to better understand a business. To keep the lesson grounded in practicality, we'll use ROE to better understand Aon plc (NYSE:AON).

Return on equity or ROE is a key measure used to assess how efficiently a company's management is utilizing the company's capital. Simply put, it is used to assess the profitability of a company in relation to its equity capital.

View our latest analysis for Aon

How Do You Calculate Return On Equity?

The formula for ROE is:

Return on Equity = Net Profit (from continuing operations) ÷ Shareholders' Equity

So, based on the above formula, the ROE for Aon is:

42% = US$2.7b ÷ US$6.4b (Based on the trailing twelve months to December 2024).

The 'return' is the amount earned after tax over the last twelve months. One way to conceptualize this is that for each $1 of shareholders' capital it has, the company made $0.42 in profit.

Does Aon Have A Good Return On Equity?

One simple way to determine if a company has a good return on equity is to compare it to the average for its industry. The limitation of this approach is that some companies are quite different from others, even within the same industry classification. As is clear from the image below, Aon has a better ROE than the average (15%) in the Insurance industry.

That's what we like to see. With that said, a high ROE doesn't always indicate high profitability. Especially when a firm uses high levels of debt to finance its debt which may boost its ROE but the high leverage puts the company at risk.

How Does Debt Impact Return On Equity?

Virtually all companies need money to invest in the business, to grow profits. The cash for investment can come from prior year profits (retained earnings), issuing new shares, or borrowing. In the first two cases, the ROE will capture this use of capital to grow. In the latter case, the debt used for growth will improve returns, but won't affect the total equity. Thus the use of debt can improve ROE, albeit along with extra risk in the case of stormy weather, metaphorically speaking.

Combining Aon's Debt And Its 42% Return On Equity

It's worth noting the high use of debt by Aon, leading to its debt to equity ratio of 2.65. There's no doubt the ROE is impressive, but it's worth keeping in mind that the metric could have been lower if the company were to reduce its debt. Debt does bring extra risk, so it's only really worthwhile when a company generates some decent returns from it.

Summary

Return on equity is useful for comparing the quality of different businesses. In our books, the highest quality companies have high return on equity, despite low debt. If two companies have around the same level of debt to equity, and one has a higher ROE, I'd generally prefer the one with higher ROE.

But ROE is just one piece of a bigger puzzle, since high quality businesses often trade on high multiples of earnings. Profit growth rates, versus the expectations reflected in the price of the stock, are a particularly important to consider. So you might want to check this FREE visualization of analyst forecasts for the company.

Of course Aon may not be the best stock to buy. So you may wish to see this free collection of other companies that have high ROE and low debt.

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This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.