Mr. Market's mood so far in 2008 hasn't benefited stock investors at all. He's been slashing and burning at the slightest hint of bad news, and now he doesn't even seem to like good news. On Tuesday, he decided that a $2.3 billion advance in Intel's (Nasdaq: INTC) bottom line was worth a decline in the company's market value of more than seven times that amount.

What's going on? Well, Mr. Market is fixated right now on the word recession, and nothing else matters. It doesn't make any difference that Intel's year-over-year profits increased by 51% to $2.3 billion on the heels of record chip sales, or that revenue rose a respectable 10% year over year to $10.7 billion.

Instead, Mr. Market accentuated the negative. Net income missed analyst expectations by $0.02 a share, and revenue fell short of what analysts wanted by $100 million. Intel also didn't seem to provide crystal-clear clarity on its outlook, and that was simply unacceptable to Wall Street. You'll see reactions like this even in steadier market environments -- a company exceeds estimates by a penny, and suddenly it's the next great growth story -- but they become magnified when things look rough.

How silly can you get?
I don't know much about Intel beyond the basics, but I do know that the company's downturn offers a wonderful reminder of how meaningless short-term results are, even when Mr. Market's tantrums may make us think otherwise. As value master Benjamin Graham and Berkshire Hathaway's (NYSE: BRK-A) (NYSE: BRK-B) Warren Buffett like to remind us, the market is a voting machine in the short term and a weighing machine in the long term. So unless there's a permanent impairment to the economics of a business, you're better off not getting wrapped up in quarterly results. They're really rather useless.

Just look at the big picture with Intel. The company reported annual revenue of more than $38 billion in 2007, yet it turns in an estimate that missed by a mere $100 million, and suddenly, some $18 billion in market value disappears. Mr. Market always hates uncertainty, but with fears of recession looming, he's viewing uncertainty as on a par with bankruptcy.

A valuable lesson
Mr. Market isn't just being a worrywart. There is legitimate reason to worry about a recession, and most investors are probably experiencing some Intel-like volatility in their portfolios as a result. But before you rush for the exits, just remember one of the most important investing lessons Graham ever gave us: "Investment is most prudent when it most business-like."

Investors were heading for those exits in 2002, even though one of the best buying opportunities in a long time was taking shape. The whole point of investing is to buy low and sell high, so investors should welcome declining markets rather than cash out. If it helps, remember that you're buying a piece of a company, not just a share that gyrates wildly each day.

What has risen shall fall, and what has fallen shall soon rise again. That old saying always holds true. All you have to do is focus on good, well-run companies and make sure the price is right. Mr. Market usually gets things right in the end, but when panic is in the air, you're bound to find some choice opportunities that have fallen through the cracks.

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