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While some investors are already well versed in financial metrics (hat tip), this article is for those who would like to learn about Return On Equity (ROE) and why it is important. By way of learning-by-doing, we'll look at ROE to gain a better understanding of Installux S.A. (EPA:STAL).

Over the last twelve months Installux has recorded a ROE of 8.5%. That means that for every €1 worth of shareholders' equity, it generated €0.085 in profit.

View our latest analysis for Installux

How Do You Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for Installux:

8.5% = €8.1m ÷ €97m (Based on the trailing twelve months to December 2018.)

Most know that net profit is the total earnings after all expenses, but the concept of shareholders' equity is a little more complicated. It is all earnings retained by the company, plus any capital paid in by shareholders. Shareholders' equity can be calculated by subtracting the total liabilities of the company from the total assets of the company.

What Does Return On Equity Mean?

ROE measures a company's profitability against the profit it retains, and any outside investments. The 'return' is the yearly profit. The higher the ROE, the more profit the company is making. So, all else being equal, a high ROE is better than a low one. Clearly, then, one can use ROE to compare different companies.

Does Installux Have A Good ROE?

By comparing a company's ROE with its industry average, we can get a quick measure of how good it is. 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, Installux has a better ROE than the average (5.6%) in the Building industry.

That's what I like to see. I usually take a closer look when a company has a better ROE than industry peers. One data point to check is if insiders have bought shares recently.

How Does Debt Impact ROE?

Companies usually need to invest money to grow their 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 use of debt will improve the returns, but will not change the equity. That will make the ROE look better than if no debt was used.

Combining Installux's Debt And Its 8.5% Return On Equity

Although Installux does use a little debt, its debt to equity ratio of just 0.044 is very low. I'm not impressed with its ROE, but the debt levels are not too high, indicating the business has decent prospects. Conservative use of debt to boost returns is usually a good move for shareholders, though it does leave the company more exposed to interest rate rises.

The Bottom Line On ROE

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. All else being equal, a higher ROE is better.

But ROE is just one piece of a bigger puzzle, since high quality businesses often trade on high multiples of earnings. It is important to consider other factors, such as future profit growth -- and how much investment is required going forward. So I think it may be worth checking this free this detailed graph of past earnings, revenue and cash flow .

If you would prefer check out another company -- one with potentially superior financials -- then do not miss this free list of interesting companies, that have HIGH return on equity and low debt.

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.