U.S. sales are down at McDonald's (NYSE: MCD)!

That's the kind of headline that's circulating today, in the wake of the Golden Arches' earnings report. What a headline -- and what a lot of negativity has hit the restaurant chain's shares.

At my last check, McDonald's shares had dropped nearly 7% on the news of this alleged "sales slowdown." As it turns out, McDonald's same-store sales were flat in December, which McDonald's attributed to severe weather and softer consumer spending. For the quarter, however, U.S. comps increased 3.3%.

Fourth-quarter net income grew 2.4% to $1.27 billion, or $1.06 per share. However, earnings included $0.33 per share in tax benefits, and currency translation boosted the earnings by another $0.04 per share. (That's right, that 74% increase in earnings from continuing operations per share isn't quite as exciting as it looks, although it's also worthwhile to mention that McDonald's still beat estimates, excluding the tax benefit.) Total revenues increased 5.7% to $5.75 billion for the quarter.

If investors are really flipping out about McDonald's flat comps growth in December, that seems a bit hysterical. Last December, McDonald's U.S. comps grew by an impressive 6.9%, and this November, a calendar shift stole a Friday from December. (Granted, the company will face some tough same-store sales comparisons in 2008, all in all.) Although comps data can be a useful tool for investors, the folly of taking one month's data and extrapolating too much from it is a pitfall investors should avoid. (Talk about short-term thinking.)

And though many are concerned about an economic slowdown, one month's comps results can't indicate that McDonald's low-priced wares aren't fairly recession-proof.

McDonald's quarter may not have been the blowout that we're accustomed to, but we don't need to worry that rivals Burger King (NYSE: BKC), Wendy's (NYSE: WEN), Yum! Brands (NYSE: YUM), and CKE Restaurants (NYSE: CKR) (home to Hardee's) are eating Mickey D's lunch just yet.    

This company has had a stupendous run, so the fact that some investors are getting cold feet isn't surprising. In truth, the significant decrease in the stock's price today might give some value-minded investors an opportunity to get in on this stalwart, well-run company -- one that also pays a dividend -- at a more reasonable price.

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