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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 JCDecaux SA (EPA:DEC).

Over the last twelve months JCDecaux has recorded a ROE of 9.5%. That means that for every €1 worth of shareholders' equity, it generated €0.095 in profit.

See our latest analysis for JCDecaux

How Do I Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for JCDecaux:

9.5% = €220m ÷ €2.5b (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 the money paid into the company from shareholders, plus any earnings retained. The easiest way to calculate shareholders' equity is to subtract the company's total liabilities from the total assets.

What Does Return On Equity Mean?

Return on Equity measures a company's profitability against the profit it has kept for the business (plus any capital injections). The 'return' is the profit over the last twelve months. A higher profit will lead to a higher ROE. So, as a general rule, a high ROE is a good thing. That means ROE can be used to compare two businesses.

Does JCDecaux Have A Good ROE?

Arguably the easiest way to assess company's ROE is to compare it with the average in its industry. The limitation of this approach is that some companies are quite different from others, even within the same industry classification. You can see in the graphic below that JCDecaux has an ROE that is fairly close to the average for the Media industry (11%).

That isn't amazing, but it is respectable. ROE doesn't tell us if the share price is low, but it can inform us to the nature of the business. For those looking for a bargain, other factors may be more important. I will like JCDecaux better if I see some big insider buys. While we wait, check out this free list of growing companies with considerable, recent, insider buying.

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 and second cases, the ROE will reflect this use of cash for investment in the business. 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 JCDecaux's Debt And Its 9.5% Return On Equity

JCDecaux has a debt to equity ratio of 0.56, which is far from excessive. The combination of modest debt and a very respectable ROE suggests this is a business worth watching. Judicious use of debt to improve returns can certainly be a good thing, although it does elevate risk slightly and reduce future optionality.

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 the same ROE, then I would generally prefer the one with less debt.

But when a business is high quality, the market often bids it up to a price that reflects this. Profit growth rates, versus the expectations reflected in the price of the stock, are a particularly important to consider. So you might want to take a peek at this data-rich interactive graph of 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.