With all the hype and hysteria surrounding the markets after the Dow Jones Industrial Average (DJINDICES:^DJI) broke the 14,000 mark last Friday, investors had the whole weekend to consider whether stock prices had gotten ahead of themselves. And based on the way the markets performed today, I think most would agree that prices have moved too high, too quickly. The Dow closed down 129 points, or 0.93%, and now sits at 13,880. The S&P 500 (SNPINDEX:^GSPC) lost 17.46 points, or 1.15%, while the Nasdaq was cut by 47.93 points, or 1.51%.

As I mentioned on Friday when the Dow shot up more than 100 points, most of the index's stocks were expected to rise. The same is true, of course, when the Dow drops more than 100 points -- very few of its 30 components will end the day in the green. This theory held true today when only one of the 30 stocks making up the Dow closed in positive territory. So let's take a look at some of the index's losers and factors that might causing them to fall lower today.

Shares of Merck (NYSE:MRK) dropped 2.34% after the stock was downgraded by analysts at Morgan Stanley and Leerink Swann. Morgan Stanley reduced the stock from a hold to a sell while citing a weak drug pipeline. Analyst David Risinger also eliminated his price target on Merck.  Leerink Swann analyst Seamus Fernandez lowered Merck to a hold from a buy. Seamus noted a number of drugs in Merck's pipeline that have a relatively high risk of not being approved by the FDA. 

Bank of America (NYSE:BAC) closed the day down 1.96% due to reports that have investors believing that the bank may face increased liabilities stemming from its mortgage practices. It currently has an agreement to pay $8.5 billion because of its Countrywide unit's mortgage abuse, but a number of Federal Home Loan Banks are arguing that this settlement is far too low.  

The personal computer giant Hewlett-Packard (NYSE:HPQ) lost 1.7% during today's trading session. Although Hewlett-Packard is the best-performing Dow stock year to date, the data supporting the growth of the PC industry is no longer available and actually points toward the industry declining. My collegue Evan Niu recently put together charts that prove that PCs are dying.

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