Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

As the Eastern U.S. braced for more inclement winter weather, stocks edged mostly higher on Tuesday. This week is remarkably light on economic reports, with Thursday's jobless claims numbers, manufacturing data, and existing home sales constituting the bulk of what investors will look to as leading indicators. Of course, earnings season is now under way, and Wall Street will be keeping a close eye on corporate America's financial health as results are released. The S&P 500 Index (^GSPC 0.26%) began its shortened week by adding 5 points, or 0.3%, to end at 1,843.

None of today's three unfortunate stocks announced earnings today, which makes their declines all the more notable. Cliffs Natural Resources (CLF -0.27%), for instance, doesn't report earnings until Feb. 13, but its shares shed 5% Tuesday as Goldman Sachs issued a forecast calling for falling metals prices. Specifically, Goldman thinks steel prices are headed off a cliff as demand from China slows and Asia's growth in the last decade is seen to be anomalistic. Although Cliffs Natural Resources doesn't exactly produce steel, it mines for the essential components of steel, which makes it just as vulnerable to the steel market. 

Shares in the online travel site Expedia (EXPE 0.62%) slumped 4.3% Tuesday in the wake of what appears to be a backlash from Google. The success of companies like Expedia rely largely on Internet searches for common phrases customers might search in attempting to book travel arrangements. Expedia's recent search traffic from such keywords is sharply down, a trend the website SearchEngineLand proposed yesterday was Google's retribution for Expedia's use of sketchy "link building" tactics the site used. Bottom line: Expedia's business may suffer as Google temporarily pushes the site's results to lower positions in its search rankings. 

Lastly, shares of United States Steel (X -0.49%) lost 2.7% Tuesday. The acute reader will remember that Goldman Sachs, upon consulting its crystal ball, kindly gave heed of a stagnant market for the future of steel. Curiously, Cliffs Natural Resources actually fell more than United States Steel did today, although in fairness coal has been going through some problems of its own recently. U.S. Steel also ended as one of the worst performers last Friday, when Citigroup noted the stock's six-month run-up and implied shares were currently overvalued. 

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