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. By way of learning-by-doing, we'll look at ROE to gain a better understanding of Xinghua Port Holdings Ltd. (HKG:1990).

Over the last twelve months Xinghua Port Holdings has recorded a ROE of 5.8%. Another way to think of that is that for every HK$1 worth of equity in the company, it was able to earn HK$0.058.

Check out our latest analysis for Xinghua Port Holdings

How Do You Calculate Return On Equity?

The formula for ROE is:

Return on Equity = Net Profit ÷ Shareholders' Equity

Or for Xinghua Port Holdings:

5.8% = CN¥51m ÷ CN¥890m (Based on the trailing twelve months to December 2018.)

It's easy to understand the 'net profit' part of that equation, but 'shareholders' equity' requires further explanation. 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 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 amount earned after tax over the last twelve months. The higher the ROE, the more profit the company is making. So, all else equal, investors should like a high ROE. That means it can be interesting to compare the ROE of different companies.

Does Xinghua Port Holdings Have A Good ROE?

Arguably the easiest way to assess company's ROE is to compare it with the average in its industry. Importantly, this is far from a perfect measure, because companies differ significantly within the same industry classification. As is clear from the image below, Xinghua Port Holdings has a lower ROE than the average (10%) in the Infrastructure industry.

Unfortunately, that's sub-optimal. We prefer it when the ROE of a company is above the industry average, but it's not the be-all and end-all if it is lower. Nonetheless, it could be useful to double-check if insiders have sold shares recently.

Why You Should Consider Debt When Looking At ROE

Companies usually need to invest money to grow their profits. That cash can come from retained earnings, issuing new shares (equity), or debt. In the case of the first and second options, the ROE will reflect this use of cash, for growth. In the latter case, the use of debt will improve the returns, but will not change the equity. That will make the ROE look better than if no debt was used.

Combining Xinghua Port Holdings's Debt And Its 5.8% Return On Equity

Although Xinghua Port Holdings does use debt, its debt to equity ratio of 0.65 is still low. I'm not impressed with its ROE, but the debt levels are not too high, indicating the business has decent prospects. 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 around the same level of debt to equity, and one has a higher ROE, I'd generally prefer the one with higher ROE.

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 this detailed graph of past earnings, revenue and cash flow .

If you would prefer check out another company -- one with potentially superior financials -- then do not miss this free list of interesting companies, that have HIGH return on equity 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.