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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. We'll use ROE to examine Zodiac Energy Limited (NSE:ZODIAC), by way of a worked example.

Our data shows Zodiac Energy has a return on equity of 15% for the last year. One way to conceptualize this, is that for each ₹1 of shareholders' equity it has, the company made ₹0.15 in profit.

See our latest analysis for Zodiac Energy

How Do You Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for Zodiac Energy:

15% = ₹31m ÷ ₹205m (Based on the trailing twelve months to March 2019.)

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 Signify?

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. 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. Clearly, then, one can use ROE to compare different companies.

Does Zodiac Energy Have A Good ROE?

One simple way to determine if a company has a good return on equity is to compare it to the average for its industry. The limitation of this approach is that some companies are quite different from others, even within the same industry classification. As you can see in the graphic below, Zodiac Energy has a higher ROE than the average (8.4%) in the Electrical industry.

That's what I like to see. In my book, a high ROE almost always warrants a closer look. One data point to check is if insiders have bought shares recently.

How Does Debt Impact ROE?

Virtually all companies need money to invest in the business, to grow profits. That cash can come from retained earnings, issuing new shares (equity), 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 use of debt will improve the returns, but will not change the equity. Thus the use of debt can improve ROE, albeit along with extra risk in the case of stormy weather, metaphorically speaking.

Combining Zodiac Energy's Debt And Its 15% Return On Equity

While Zodiac Energy does have some debt, with debt to equity of just 0.20, we wouldn't say debt is excessive. Its ROE isn't particularly impressive, but the debt levels are quite modest, so the business probably has some real potential. Judicious use of debt to improve returns can certainly be a good thing, although it does elevate risk slightly and reduce future optionality.

But It's Just One Metric

Return on equity is one way we can compare the business quality of different companies. In my book the highest quality companies have high return on equity, despite low debt. If two companies have the same ROE, then I would generally prefer the one with less debt.

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. You can see how the company has grow in the past by looking at this FREE detailed graph of past earnings, revenue and cash flow.

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.