As an investor, mistakes are inevitable. But really big losses can really drag down an overall portfolio. So spare a thought for the long term shareholders of ImpediMed Limited (ASX:IPD); the share price is down a whopping 80% in the last three years. That'd be enough to cause even the strongest minds some disquiet. More recently, the share price has dropped a further 11% in a month.

While a drop like that is definitely a body blow, money isn't as important as health and happiness.

Check out our latest analysis for ImpediMed

ImpediMed isn't currently profitable, so most analysts would look to revenue growth to get an idea of how fast the underlying business is growing. Generally speaking, companies without profits are expected to grow revenue every year, and at a good clip. That's because it's hard to be confident a company will be sustainable if revenue growth is negligible, and it never makes a profit.

In the last three years ImpediMed saw its revenue shrink by 14% per year. That is not a good result. The share price fall of 42% (per year, over three years) is a stern reminder that money-losing companies are expected to grow revenue. We're generally averse to companies with declining revenues, but we're not alone in that. Don't let a share price decline ruin your calm. You make better decisions when you're calm.

The company's revenue and earnings (over time) are depicted in the image below (click to see the exact numbers).

You can see how its balance sheet has strengthened (or weakened) over time in this free interactive graphic.

A Different Perspective

ImpediMed shareholders are down 19% for the year, but the market itself is up 25%. 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, longer term shareholders are suffering worse, given the loss of 27% doled out over the last five years. We would want clear information suggesting the company will grow, before taking the view that the share price will stabilize. It's always interesting to track share price performance over the longer term. But to understand ImpediMed better, we need to consider many other factors. To that end, you should learn about the 5 warning signs we've spotted with ImpediMed (including 1 which is can't be ignored) .

If you would prefer to check out another company -- one with potentially superior financials -- then do not miss this free list of companies that have proven they can grow earnings.