This week we saw the Sleep Number Corporation (NASDAQ:SNBR) share price climb by 22%. But that doesn't change the fact that the returns over the last three years have been stomach churning. To wit, the share price sky-dived 89% in that time. So we're relieved for long term holders to see a bit of uplift. Only time will tell if the company can sustain the turnaround. We really hope anyone holding through that price crash has a diversified portfolio. Even when you lose money, you don't have to lose the lesson.

While the stock has risen 22% in the past week but long term shareholders are still in the red, let's see what the fundamentals can tell us.

Check out our latest analysis for Sleep Number

While markets are a powerful pricing mechanism, share prices reflect investor sentiment, not just underlying business performance. One flawed but reasonable way to assess how sentiment around a company has changed is to compare the earnings per share (EPS) with the share price.

Sleep Number saw its share price decline over the three years in which its EPS also dropped, falling to a loss. Since the company has fallen to a loss making position, it's hard to compare the change in EPS with the share price change. But it's safe to say we'd generally expect the share price to be lower as a result!

The company's earnings per share (over time) is depicted in the image below (click to see the exact numbers).

We consider it positive that insiders have made significant purchases in the last year. Even so, future earnings will be far more important to whether current shareholders make money. Before buying or selling a stock, we always recommend a close examination of historic growth trends, available here..

A Different Perspective

Investors in Sleep Number had a tough year, with a total loss of 72%, against a market gain of about 22%. Even the share prices of good stocks drop sometimes, but we want to see improvements in the fundamental metrics of a business, before getting too interested. Unfortunately, last year's performance may indicate unresolved challenges, given that it was worse than the annualised loss of 12% over the last half decade. Generally speaking long term share price weakness can be a bad sign, though contrarian investors might want to research the stock in hope of a turnaround. 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. Like risks, for instance. Every company has them, and we've spotted 3 warning signs for Sleep Number (of which 2 are concerning!) you should know about.