The Detection Technology Oyj (HEL:DETEC) share price has done well in the last month, posting a gain of 31%. That brought the twelve month gain to a very sharp 61%.

Assuming no other changes, a sharply higher share price makes a stock less attractive to potential buyers. 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). So some would prefer to hold off buying when there is a lot of optimism towards a stock. 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.

View our latest analysis for Detection Technology Oyj

Does Detection Technology Oyj Have A Relatively High Or Low P/E For Its Industry?

We can tell from its P/E ratio of 26.96 that there is some investor optimism about Detection Technology Oyj. You can see in the image below that the average P/E (11.2) for companies in the electronic industry is lower than Detection Technology Oyj's P/E.

Detection Technology Oyj'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 investors should delve deeper. I like to check if company insiders have been buying or 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. So while a stock may look expensive based on past earnings, it could be cheap based on future earnings.

Detection Technology Oyj saw earnings per share decrease by 16% last year. But over the longer term (5 years) earnings per share have increased by 28%.

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

The 'Price' in P/E reflects the market capitalization of the company. So it won't reflect the advantage of cash, or disadvantage of debt. 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.

How Does Detection Technology Oyj's Debt Impact Its P/E Ratio?

Detection Technology Oyj has net cash of €11m. That should lead to a higher P/E than if it did have debt, because its strong balance sheets gives it more options.