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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). We'll use ROE to examine Microwave Vision S.A. (EPA:ALMIC), by way of a worked example.

Over the last twelve months Microwave Vision has recorded a ROE of 7.2%. That means that for every €1 worth of shareholders' equity, it generated €0.072 in profit.

See our latest analysis for Microwave Vision

How Do I Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for Microwave Vision:

7.2% = €4.8m ÷ €69m (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 all earnings retained by the company, plus any capital paid in by shareholders. The easiest way to calculate shareholders' equity is to subtract the company's total liabilities from the total assets.

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. That means that the higher the ROE, the more profitable the company is. So, as a general rule, a high ROE is a good thing. That means it can be interesting to compare the ROE of different companies.

Does Microwave Vision Have A Good Return On Equity?

By comparing a company's ROE with its industry average, we can get a quick measure of how good it is. The limitation of this approach is that some companies are quite different from others, even within the same industry classification. If you look at the image below, you can see Microwave Vision has a lower ROE than the average (9.0%) in the Communications industry classification.

That certainly isn't ideal. It is better when the ROE is above industry average, but a low one doesn't necessarily mean the business is overpriced. Nonetheless, it might be wise to check if insiders have been selling.

Why You Should Consider Debt When Looking At 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 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. Thus the use of debt can improve ROE, albeit along with extra risk in the case of stormy weather, metaphorically speaking.

Combining Microwave Vision's Debt And Its 7.2% Return On Equity

Although Microwave Vision does use a little debt, its debt to equity ratio of just 0.068 is very low. Its ROE isn't particularly impressive, but the debt levels are quite modest, so the business probably has some real potential. 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 useful for comparing the quality of different businesses. A company that can achieve a high return on equity without debt could be considered a high quality business. 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 I think it may be worth checking this free report on 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.