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 Century Aluminum (NASDAQ:CENX) fell 10% today, after an analyst downgraded the stock.

So what: CRT Capital downgraded Century Aluminum to sell from fair value, and put a price target of $7 on the stock. That would be more than a 25% downside from yesterday's closing price.  

Now what: At The Motley Fool, we don't take analyst ratings too seriously, because investors tend to only react to them on a short-term basis. The company is in a transition from serious losses to hopefully a small profit in 2013, which would have me leery no matter what the analysts say. Alcoa's (NYSE:AA) earnings report was generally positive to start earnings season, so keep an eye on the trends when Century reports fourth quarter 2012 and first quarter 2013 earnings. The company has met or beaten expectations each of the last four quarters, so surprises on the upside would be a great operational sign for the company. I'm not a buyer today but, if the next two quarters look good, the company could have strong operational momentum.

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