Many investors are still learning about the various metrics that can be useful when analysing a stock. This article is for those who would like to learn about Return On Equity (ROE). To keep the lesson grounded in practicality, we'll use ROE to better understand Voltalia SA (EPA:VLTSA).

Our data shows Voltalia has a return on equity of 1.6% for the last year. Another way to think of that is that for every €1 worth of equity in the company, it was able to earn €0.016.

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See our latest analysis for Voltalia

How Do I Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for Voltalia:

1.6% = €8.5m ÷ €372m (Based on the trailing twelve months to December 2018.)

Most readers would understand what net profit is, but it’s worth explaining the concept of shareholders’ equity. It is the capital paid in by shareholders, plus any retained earnings. Shareholders' equity can be calculated by subtracting the total liabilities of the company from the total assets of the company.

What Does ROE Mean?

ROE measures a company's profitability against the profit it retains, and any outside investments. The 'return' is the amount earned after tax over the last twelve months. A higher profit will lead to a higher ROE. So, all else equal, investors should like a high ROE. That means it can be interesting to compare the ROE of different companies.

Does Voltalia Have A Good Return On Equity?

Arguably the easiest way to assess company's ROE is to compare it with the average in its industry. However, this method is only useful as a rough check, because companies do differ quite a bit within the same industry classification. As is clear from the image below, Voltalia has a lower ROE than the average (2.6%) in the Renewable Energy industry.

Unfortunately, that's sub-optimal. We prefer it when the ROE of a company is above the industry average, but it's not the be-all and end-all if it is lower. Nonetheless, it might be wise to check if insiders have been selling.

The Importance Of Debt To Return On Equity

Virtually all companies need money to invest in the business, to grow profits. That cash can come from issuing shares, retained earnings, or debt. In the first and second cases, the ROE will reflect this use of cash for investment in the business. 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.

Voltalia's Debt And Its 1.6% ROE

Voltalia does use a significant amount of debt to increase returns. It has a debt to equity ratio of 1.37. With a fairly low ROE, and significant use of debt, it's hard to get excited about this business at the moment. Investors should think carefully about how a company might perform if it was unable to borrow so easily, because credit markets do change over time.

In Summary

Return on equity is one way we can compare the business quality of different companies. Companies that can achieve high returns on equity without too much debt are generally of good quality. 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.

Having said that, while ROE is a useful indicator of business quality, you'll have to look at a whole range of factors to determine the right price to buy a stock. It is important to consider other factors, such as future profit growth -- and how much investment is required going forward. So you might want to check this FREE visualization of analyst forecasts for the company.

Of course, you might find a fantastic investment by looking elsewhere. So take a peek at this free list of interesting companies.

We aim to bring you long-term focused research analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material.

If you spot an error that warrants correction, please contact the editor at editorial-team@simplywallst.com. This article by Simply Wall St is general in nature. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. Simply Wall St has no position in the stocks mentioned. Thank you for reading.