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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 China Mengniu Dairy Company Limited (HKG:2319), by way of a worked example.

China Mengniu Dairy has a ROE of 11%, based on the last twelve months. Another way to think of that is that for every HK$1 worth of equity in the company, it was able to earn HK$0.11.

Check out our latest analysis for China Mengniu Dairy

How Do You Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for China Mengniu Dairy:

11% = CN¥3.0b ÷ CN¥30b (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. 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 profit over the last twelve months. That means that the higher the ROE, the more profitable the company is. So, all else being equal, a high ROE is better than a low one. That means it can be interesting to compare the ROE of different companies.

Does China Mengniu Dairy Have A Good Return On Equity?

One simple way to determine if a company has a good return on equity is to compare it to the average for its industry. Importantly, this is far from a perfect measure, because companies differ significantly within the same industry classification. If you look at the image below, you can see China Mengniu Dairy has a similar ROE to the average in the Food industry classification (8.9%).

That's neither particularly good, nor bad. ROE tells us about the quality of the business, but it does not give us much of an idea if the share price is cheap. For those who like to find winning investments this free list of growing companies with recent insider purchasing, could be just the ticket.

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 two cases, the ROE will capture this use of capital to grow. In the latter case, the debt used for growth will improve returns, but won't affect the total equity. In this manner the use of debt will boost ROE, even though the core economics of the business stay the same.

Combining China Mengniu Dairy's Debt And Its 11% Return On Equity

While China Mengniu Dairy does have some debt, with debt to equity of just 0.48, we wouldn't say debt is excessive. The fact that it achieved a fairly good ROE with only modest debt suggests the business might be worth putting on your watchlist. 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.

But It's Just One Metric

Return on equity is useful for comparing the quality of different businesses. 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 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 check this FREE visualization of analyst forecasts for the company.

Of course China Mengniu Dairy may not be the best stock to buy. So you may wish to see this free collection of other companies that have high ROE 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.