One of the best investments we can make is in our own knowledge and skill set. With that in mind, this article will work through how we can use Return On Equity (ROE) to better understand a business. We'll use ROE to examine China State Construction Development Holdings Limited (HKG:830), by way of a worked example.

Over the last twelve months China State Construction Development Holdings has recorded a ROE of 14%. One way to conceptualize this, is that for each HK$1 of shareholders' equity it has, the company made HK$0.14 in profit.

Check out our latest analysis for China State Construction Development Holdings

How Do I Calculate Return On Equity?

The formula for return on equity is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for China State Construction Development Holdings:

14% = HK$149m ÷ HK$1.0b (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 the capital paid in by shareholders, plus any retained earnings. 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 looks at the amount a company earns relative to the money it has kept within the business. 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 ROE can be used to compare two businesses.

Does China State Construction Development Holdings 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. Importantly, this is far from a perfect measure, because companies differ significantly within the same industry classification. As you can see in the graphic below, China State Construction Development Holdings has a higher ROE than the average (5.5%) in the Building 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.

The Importance Of Debt To 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 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.

China State Construction Development Holdings's Debt And Its 14% ROE

While China State Construction Development Holdings does have some debt, with debt to equity of just 0.69, we wouldn't say debt is excessive. Its very respectable ROE, combined with only modest debt, suggests the business is in good shape. 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. In my book the highest quality companies have high return on equity, despite low debt. 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. 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 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.