This article is written for those who want to get better at using price to earnings ratios (P/E ratios). We'll apply a basic P/E ratio analysis to Sino Gas Holdings Group Limited's (HKG:1759), to help you decide if the stock is worth further research. Sino Gas Holdings Group has a P/E ratio of 15.75, based on the last twelve months. In other words, at today's prices, investors are paying HK$15.75 for every HK$1 in prior year profit.

See our latest analysis for Sino Gas Holdings Group

How Do You Calculate A P/E Ratio?

The formula for P/E is:

Price to Earnings Ratio = Price per Share (in the reporting currency) ÷ Earnings per Share (EPS)

Or for Sino Gas Holdings Group:

P/E of 15.75 = CN¥2.44 (Note: this is the share price in the reporting currency, namely, CNY ) ÷ CN¥0.16 (Based on the trailing twelve months to June 2019.)

Is A High Price-to-Earnings Ratio Good?

A higher P/E ratio means that buyers have to pay a higher price for each HK$1 the company has earned over the last year. All else being equal, it's better to pay a low price -- but as Warren Buffett said, 'It's far better to buy a wonderful company at a fair price than a fair company at a wonderful price.'

Does Sino Gas Holdings Group Have A Relatively High Or Low P/E For Its Industry?

We can get an indication of market expectations by looking at the P/E ratio. As you can see below, Sino Gas Holdings Group has a higher P/E than the average company (12) in the specialty retail industry.

Sino Gas Holdings Group's P/E tells us that market participants think the company will perform better than its industry peers, going forward. The market is optimistic about the future, but that doesn't guarantee future growth. So further research is always essential. I often monitor director buying and selling.

How Growth Rates Impact P/E Ratios

Earnings growth rates have a big influence on P/E ratios. When earnings grow, the 'E' increases, over time. And in that case, the P/E ratio itself will drop rather quickly. Then, a lower P/E should attract more buyers, pushing the share price up.

Sino Gas Holdings Group shrunk earnings per share by 59% over the last year.

A Limitation: P/E Ratios Ignore Debt and Cash In The Bank

It's important to note that the P/E ratio considers the market capitalization, not the enterprise value. In other words, it does not consider any debt or cash that the company may have on the balance sheet. Theoretically, a business can improve its earnings (and produce a lower P/E in the future) by investing in growth. That means taking on debt (or spending its cash).

Spending on growth might be good or bad a few years later, but the point is that the P/E ratio does not account for the option (or lack thereof).

Sino Gas Holdings Group's Balance Sheet

Since Sino Gas Holdings Group holds net cash of CN¥18m, it can spend on growth, justifying a higher P/E ratio than otherwise.

The Bottom Line On Sino Gas Holdings Group's P/E Ratio

Sino Gas Holdings Group trades on a P/E ratio of 15.7, which is above its market average of 10.6. Falling earnings per share is probably keeping traditional value investors away, but the healthy balance sheet means the company retains potential for future growth. If fails to eventuate, the current high P/E could prove to be temporary, as the share price falls.

Investors have an opportunity when market expectations about a stock are wrong. People often underestimate remarkable growth -- so investors can make money when fast growth is not fully appreciated. We don't have analyst forecasts, but you might want to assess this data-rich visualization of earnings, revenue and cash flow.

Of course, you might find a fantastic investment by looking at a few good candidates. So take a peek at this free list of companies with modest (or no) debt, trading on a P/E below 20.

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.