The IDT Corporation (NYSE:IDT) share price has done very well over the last month, posting an excellent gain of 25%. Looking back a bit further, it's encouraging to see the stock is up 70% in the last year.

Even after such a large jump in price, you could still be forgiven for feeling indifferent about IDT's P/E ratio of 18.3x, since the median price-to-earnings (or "P/E") ratio in the United States is also close to 18x. Although, it's not wise to simply ignore the P/E without explanation as investors may be disregarding a distinct opportunity or a costly mistake.

Recent times have been quite advantageous for IDT as its earnings have been rising very briskly. The P/E is probably moderate because investors think this strong earnings growth might not be enough to outperform the broader market in the near future. If that doesn't eventuate, then existing shareholders have reason to be feeling optimistic about the future direction of the share price.

How Is IDT's Growth Trending?

In order to justify its P/E ratio, IDT would need to produce growth that's similar to the market.

Taking a look back first, we see that the company grew earnings per share by an impressive 61% last year. However, this wasn't enough as the latest three year period has seen a very unpleasant 33% drop in EPS in aggregate. Accordingly, shareholders would have felt downbeat about the medium-term rates of earnings growth.

Weighing that medium-term earnings trajectory against the broader market's one-year forecast for expansion of 14% shows it's an unpleasant look.

With this information, we find it concerning that IDT is trading at a fairly similar P/E to the market. It seems most investors are ignoring the recent poor growth rate and are hoping for a turnaround in the company's business prospects. There's a good chance existing shareholders are setting themselves up for future disappointment if the P/E falls to levels more in line with the recent negative growth rates.

The Bottom Line On IDT's P/E

Its shares have lifted substantially and now IDT's P/E is also back up to the market median. 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.

Our examination of IDT revealed its shrinking earnings over the medium-term aren't impacting its P/E as much as we would have predicted, given the market is set to grow. Right now we are uncomfortable with the P/E as this earnings performance is unlikely to support a more positive sentiment for long. Unless the recent medium-term conditions improve, it's challenging to accept these prices as being reasonable.

You always need to take note of risks, for example - IDT has 1 warning sign we think you should be aware of.

If P/E ratios interest you, you may wish to see this free collection of other companies with strong earnings growth and low P/E ratios.

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.