The main aim of stock picking is to find the market-beating stocks. But every investor is virtually certain to have both over-performing and under-performing stocks. So we wouldn't blame long term Proto Labs, Inc. (NYSE:PRLB) shareholders for doubting their decision to hold, with the stock down 46% over a half decade.

Now let's have a look at the company's fundamentals, and see if the long term shareholder return has matched the performance of the underlying business.

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In his essay The Superinvestors of Graham-and-Doddsville Warren Buffett described how share prices do not always rationally reflect the value of a business. One imperfect but simple way to consider how the market perception of a company has shifted is to compare the change in the earnings per share (EPS) with the share price movement.

Looking back five years, both Proto Labs' share price and EPS declined; the latter at a rate of 22% per year. This fall in the EPS is worse than the 12% compound annual share price fall. So investors might expect EPS to bounce back -- or they may have previously foreseen the EPS decline. The high P/E ratio of 54.11 suggests that shareholders believe earnings will grow in the years ahead.

The image below shows how EPS has tracked over time (if you click on the image you can see greater detail).

Before buying or selling a stock, we always recommend a close examination of historic growth trends, available here.

A Different Perspective

Proto Labs shareholders gained a total return of 3.6% during the year. But that was short of the market average. On the bright side, that's still a gain, and it is certainly better than the yearly loss of about 8% endured over half a decade. So this might be a sign the business has turned its fortunes around. Before spending more time on Proto Labs it might be wise to click here to see if insiders have been buying or selling shares.

For those who like to find winning investments this free list of undervalued companies with recent insider purchasing, could be just the ticket.

Please note, the market returns quoted in this article reflect the market weighted average returns of stocks that currently trade on American exchanges.

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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.