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: Shares of office supply retailer Staples (Nasdaq: SPLS) plummeted 16% on Wednesday after its quarterly results and full-year outlook came in below Wall Street estimates.

So what: Hurt primarily by weaker-than-expected sales, the company posted a first-quarter profit of $198.2 million, or $0.28 per share, versus the average analyst estimate of $0.32 per share. With the miss coming less than a month after smaller foes Office Depot (NYSE: ODP) and OfficeMax (NYSE: OMX) also reported disappointing quarters, investors seem to be worried that the office supply space, as a whole, might be facing a more serious secular decline.    

Now what: Management now sees full-year earnings of between $1.35 and $1.45 per share. Although the outlook also came in below Wall Street estimates, today's big sell-off leaves the stock trading at less than 12 times the midpoint of that range, suggesting a possible opportunity. While the overall revenue trend is concerning, Staples' continued market share gains in North America and better-than-expected international sales are a pair of positives value hunters can hang their hat on.

Interested in more info on Staples? Add it to your watchlist.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Motley Fool newsletter services have recommended Staples. Try any of our Foolish newsletter services free for 30 days.

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