Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Great Atlantic & Pacific Tea Co. (NYSE: GAP) shares are up nearly 5.2% in afternoon trading on no news. 

So What: The company, which owns the A&P supermarket chain, reported a big quarterly loss last week, roughly double its loss a year ago, as sales continue to decline. Despite the gloom, investors were cheered by the company's progress with its turnaround. Since that report, Great Atlantic & Pacific Tea shares are up 20%.

Now What: Today's pop may reflect continued buying on the positive turnaround news reported last week, but keep an eye out for not yet released news.   

Interested in more info on Great Atlantic & Pacific? Add it to your watchlist here by clicking here.

Fool contributor, April Taylor, does not own shares of the companies mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.