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. We'll use ROE to examine Diageo plc (LON:DGE), by way of a worked example.

Return on Equity or ROE is a test of how effectively a company is growing its value and managing investors’ money. Put another way, it reveals the company's success at turning shareholder investments into profits.

Check out our latest analysis for Diageo

How Is ROE Calculated?

The formula for ROE is:

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

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

35% = UK£3.3b ÷ UK£9.5b (Based on the trailing twelve months to June 2022).

The 'return' is the income the business earned over the last year. That means that for every £1 worth of shareholders' equity, the company generated £0.35 in profit.

Does Diageo 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. Importantly, this is far from a perfect measure, because companies differ significantly within the same industry classification. As you can see in the graphic below, Diageo has a higher ROE than the average (13%) in the Beverage industry.

That's clearly a positive. With that said, a high ROE doesn't always indicate high profitability. A higher proportion of debt in a company's capital structure may also result in a high ROE, where the high debt levels could be a huge risk .

How Does Debt Impact ROE?

Most companies need money -- from somewhere -- to grow their profits. The cash for investment can come from prior year profits (retained earnings), issuing new shares, or borrowing. In the case of the first and second options, the ROE will reflect this use of cash, for growth. In the latter case, the debt required for growth will boost returns, but will not impact the shareholders' equity. That will make the ROE look better than if no debt was used.

Diageo's Debt And Its 35% ROE

It's worth noting the high use of debt by Diageo, leading to its debt to equity ratio of 1.71. 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 increases risk and reduces options for the company in the future, so you generally want to see some good returns from using it.

Conclusion

Return on equity is a useful indicator of the ability of a business to generate profits and return them to shareholders. Companies that can achieve high returns on equity without too much debt are generally of good quality. If two companies have the same ROE, then I would generally prefer the one with less debt.