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: One day after URS Corp. (NYSE: URS) reported an 8% rise in second-quarter profit, its share price slipped 10% in early trading today.

So what: The construction company earned $0.86 per share in the quarter, and yes, that was more than it earned last year. Problem was, it wasn't quite enough to satisfy investors' desire for $0.92 per share profit. (Revenue also fell about $100 million short of consensus estimates.)

Now what: At 10 times earnings, and with long-term growth estimates hovering around 11%, URS shares look cheap -- except for one thing. CEO Martin Koffel mentioned in the earnings report that he's confident in URS' ability to grow over the long term through doing "federal and infrastructure work." Show of hands: How many of you out there are confident that a cash-strapped federal government is going to spend all the money that URS hopes to receive?

And there you have it, folks: The second reason for the sell-off.

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