To the annoyance of some shareholders, BOC Aviation (HKG:2588) shares are down a considerable 31% in the last month. The recent drop has obliterated the annual return, with the share price now down 17% over that longer period.

All else being equal, a share price drop should make a stock more attractive to potential investors. In the long term, share prices tend to follow earnings per share, but in the short term prices bounce around in response to short term factors (which are not always obvious). The implication here is that long term investors have an opportunity when expectations of a company are too low. One way to gauge market expectations of a stock is to look at its Price to Earnings Ratio (PE Ratio). A high P/E implies that investors have high expectations of what a company can achieve compared to a company with a low P/E ratio.

See our latest analysis for BOC Aviation

Does BOC Aviation Have A Relatively High Or Low P/E For Its Industry?

We can tell from its P/E ratio of 6.61 that sentiment around BOC Aviation isn't particularly high. We can see in the image below that the average P/E (8.1) for companies in the trade distributors industry is higher than BOC Aviation's P/E.

BOC Aviation's P/E tells us that market participants think it will not fare as well as its peers in the same industry. While current expectations are low, the stock could be undervalued if the situation is better than the market assumes. It is arguably worth checking if insiders are buying shares, because that might imply they believe the stock is undervalued.

How Growth Rates Impact P/E Ratios

Generally speaking the rate of earnings growth has a profound impact on a company's P/E multiple. That's because companies that grow earnings per share quickly will rapidly increase the 'E' in the equation. Therefore, even if you pay a high multiple of earnings now, that multiple will become lower in the future. A lower P/E should indicate the stock is cheap relative to others -- and that may attract buyers.

Most would be impressed by BOC Aviation earnings growth of 13% in the last year. And it has bolstered its earnings per share by 14% per year over the last five years. With that performance, you might expect an above average P/E ratio.

Don't Forget: The P/E Does Not Account For Debt or Bank Deposits

It's important to note that the P/E ratio considers the market capitalization, not the enterprise value. That means it doesn't take debt or cash into account. The exact same company would hypothetically deserve a higher P/E ratio if it had a strong balance sheet, than if it had a weak one with lots of debt, because a cashed up company can spend on growth.