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. To keep the lesson grounded in practicality, we'll use ROE to better understand Zynex, Inc. (NASDAQ:ZYXI).

ROE or return on equity is a useful tool to assess how effectively a company can generate returns on the investment it received from its shareholders. Put another way, it reveals the company's success at turning shareholder investments into profits.

View our latest analysis for Zynex

How Is ROE Calculated?

ROE can be calculated by using the formula:

Return on Equity = Net Profit (from continuing operations) ÷ Shareholders' Equity

So, based on the above formula, the ROE for Zynex is:

13% = US$4.8m ÷ US$36m (Based on the trailing twelve months to September 2024).

The 'return' is the amount earned after tax over the last twelve months. Another way to think of that is that for every $1 worth of equity, the company was able to earn $0.13 in profit.

Does Zynex 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. If you look at the image below, you can see Zynex has a similar ROE to the average in the Medical Equipment industry classification (12%).

That's neither particularly good, nor bad. Although the ROE is similar to the industry, we should still perform further checks to see if the company's ROE is being boosted by high debt levels. If a company takes on too much debt, it is at higher risk of defaulting on interest payments. Our risks dashboardshould have the 2 risks we have identified for Zynex.

How Does Debt Impact ROE?

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. That will make the ROE look better than if no debt was used.

Zynex's Debt And Its 13% ROE

Zynex clearly uses a high amount of debt to boost returns, as it has a debt to equity ratio of 1.63. While its ROE is respectable, it is worth keeping in mind that there is usually a limit as to how much debt a company can use. Debt does bring extra risk, so it's only really worthwhile when a company generates some decent returns from it.

Summary

Return on equity is useful for comparing the quality of different businesses. In our books, the highest quality companies have high return on equity, despite low debt. All else being equal, a higher ROE is better.

But ROE is just one piece of a bigger puzzle, since high quality businesses often trade on high multiples of earnings. It is important to consider other factors, such as future profit growth -- and how much investment is required going forward. So you might want to take a peek at this data-rich interactive graph of forecasts for the company.

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.

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This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.