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What: Shares of Wolverine World Wide (NYSE: WWW) have gotten crushed today, down by as much as 10%, after the company warned about weakness in European markets.

So what: Roughly a quarter of last year's sales were generated in Europe, so weakness there could certainly hurt the footwear and apparel maker's results. At a retail conference, Wolverine World Wide disclosed that it will "fall modestly below" its prior guidance primarily due to continued challenges it faces in Europe.

Now what: Europe, Middle East, and Africa sales so far this quarter have fallen by double digits relative to a year ago. The company cited a combination of weather and economic conditions as contributing factors. Previous guidance called for low-to-mid-single-digit revenue growth and roughly flat earnings, but Wolverine now concedes it can't hit that target. On the bright side, the U.S. wholesale business "remains solid," but that's little consolation to shareholders today.

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