Unfortunately for some shareholders, the Alten (EPA:ATE) share price has dived 48% in the last thirty days. That drop has capped off a tough year for shareholders, with the share price down 39% in that time.

All else being equal, a share price drop should make a stock more attractive to potential investors. While the market sentiment towards a stock is very changeable, in the long run, the share price will tend to move in the same direction as earnings per share. The implication here is that long term investors have an opportunity when expectations of a company are too low. Perhaps the simplest way to get a read on investors' expectations of a business is to look at its Price to Earnings Ratio (PE Ratio). A high P/E ratio means that investors have a high expectation about future growth, while a low P/E ratio means they have low expectations about future growth.

Check out our latest analysis for Alten

How Does Alten's P/E Ratio Compare To Its Peers?

Alten has a P/E ratio of 12.16. As you can see below Alten has a P/E ratio that is fairly close for the average for the it industry, which is 12.2.

That indicates that the market expects Alten will perform roughly in line with other companies in its industry. The company could surprise by performing better than average, in the future. Further research into factors such as insider buying and selling, could help you form your own view on whether that is likely.

How Growth Rates Impact P/E Ratios

Probably the most important factor in determining what P/E a company trades on is the earnings growth. That's because companies that grow earnings per share quickly will rapidly increase the 'E' in the equation. That means even if the current P/E is high, it will reduce over time if the share price stays flat. Then, a lower P/E should attract more buyers, pushing the share price up.

Alten saw earnings per share improve by 6.9% last year. And earnings per share have improved by 15% annually, over the last five years.

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

One drawback of using a P/E ratio is that it considers market capitalization, but not the balance sheet. 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).

Such spending might be good or bad, overall, but the key point here is that you need to look at debt to understand the P/E ratio in context.