It's not a stretch to say that Jiangsu Expressway Company Limited's (HKG:177) price-to-earnings (or "P/E") ratio of 8.1x right now seems quite "middle-of-the-road" compared to the market in Hong Kong, where the median P/E ratio is around 10x. However, investors might be overlooking a clear opportunity or potential setback if there is no rational basis for the P/E.

While the market has experienced earnings growth lately, Jiangsu Expressway's earnings have gone into reverse gear, which is not great. One possibility is that the P/E is moderate because investors think this poor earnings performance will turn around. You'd really hope so, otherwise you're paying a relatively elevated price for a company with this sort of growth profile.

View our latest analysis for Jiangsu Expressway

If you'd like to see what analysts are forecasting going forward, you should check out our free report on Jiangsu Expressway.

What Are Growth Metrics Telling Us About The P/E?

There's an inherent assumption that a company should be matching the market for P/E ratios like Jiangsu Expressway's to be considered reasonable.

If we review the last year of earnings, dishearteningly the company's profits fell to the tune of 3.3%. At least EPS has managed not to go completely backwards from three years ago in aggregate, thanks to the earlier period of growth. Accordingly, shareholders probably wouldn't have been overly satisfied with the unstable medium-term growth rates.

Turning to the outlook, the next year should generate growth of 11% as estimated by the six analysts watching the company. That's shaping up to be materially lower than the 23% growth forecast for the broader market.

With this information, we find it interesting that Jiangsu Expressway is trading at a fairly similar P/E to the market. Apparently many investors in the company are less bearish than analysts indicate and aren't willing to let go of their stock right now. Maintaining these prices will be difficult to achieve as this level of earnings growth is likely to weigh down the shares eventually.

The Key Takeaway

Using the price-to-earnings ratio alone to determine if you should sell your stock isn't sensible, however it can be a practical guide to the company's future prospects.

We've established that Jiangsu Expressway currently trades on a higher than expected P/E since its forecast growth is lower than the wider market. When we see a weak earnings outlook with slower than market growth, we suspect the share price is at risk of declining, sending the moderate P/E lower. This places shareholders' investments at risk and potential investors in danger of paying an unnecessary premium.

You always need to take note of risks, for example - Jiangsu Expressway has 2 warning signs we think you should be aware of.

If you're unsure about the strength of Jiangsu Expressway's business, why not explore our interactive list of stocks with solid business fundamentals for some other companies you may have missed.

Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email editorial-team (at) simplywallst.com.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.