When you buy and hold a stock for the long term, you definitely want it to provide a positive return. But more than that, you probably want to see it rise more than the market average. Unfortunately for shareholders, while the Power Integrations, Inc. (NASDAQ:POWI) share price is up 77% in the last five years, that's less than the market return. Zooming in, the stock is actually down 21% in the last year.

So let's assess the underlying fundamentals over the last 5 years and see if they've moved in lock-step with shareholder returns.

See our latest analysis for Power Integrations

To paraphrase Benjamin Graham: Over the short term the market is a voting machine, but over the long term it's a weighing machine. By comparing earnings per share (EPS) and share price changes over time, we can get a feel for how investor attitudes to a company have morphed over time.

Power Integrations' earnings per share are down 2.9% per year, despite strong share price performance over five years.

So it's hard to argue that the earnings per share are the best metric to judge the company, as it may not be optimized for profits at this point. Therefore, it's worth taking a look at other metrics to try to understand the share price movements.

The modest 1.1% dividend yield is unlikely to be propping up the share price. On the other hand, Power Integrations' revenue is growing nicely, at a compound rate of 5.8% over the last five years. In that case, the company may be sacrificing current earnings per share to drive growth.

The image below shows how earnings and revenue have tracked over time (if you click on the image you can see greater detail).

This free interactive report on Power Integrations' balance sheet strength is a great place to start, if you want to investigate the stock further.

What About Dividends?

It is important to consider the total shareholder return, as well as the share price return, for any given stock. Whereas the share price return only reflects the change in the share price, the TSR includes the value of dividends (assuming they were reinvested) and the benefit of any discounted capital raising or spin-off. It's fair to say that the TSR gives a more complete picture for stocks that pay a dividend. In the case of Power Integrations, it has a TSR of 85% for the last 5 years. That exceeds its share price return that we previously mentioned. And there's no prize for guessing that the dividend payments largely explain the divergence!

A Different Perspective

Investors in Power Integrations had a tough year, with a total loss of 21% (including dividends), against a market gain of about 26%. However, keep in mind that even the best stocks will sometimes underperform the market over a twelve month period. On the bright side, long term shareholders have made money, with a gain of 13% per year over half a decade. If the fundamental data continues to indicate long term sustainable growth, the current sell-off could be an opportunity worth considering. I find it very interesting to look at share price over the long term as a proxy for business performance. But to truly gain insight, we need to consider other information, too. Consider risks, for instance. Every company has them, and we've spotted 2 warning signs for Power Integrations you should know about.