After a few terrible trading sessions last week, the bearish sentiment was back on Wall Street again today. As the closing bell rang today, the Dow Jones Industrial Average (^DJI -1.39%) was lower by 139 points, or 0.94%. But as bad as that may seem, the Dow was down as many as 248 points. The other two major indexes also performed poorly, as the S&P 500 lost 1.21% and the Nasdaq fell lower by 1.09%.

The Federal Reserve and its announcement that it will soon begin slowing stimulus surely is still playing on investors' minds today, but it's more conceivable that the Chinese government's decision to allow its country's markets to work through a credit crunch was the real cause for the declines in the U.S. markets.

A few Dow losers
Shares of Boeing (BA -1.35%) fell 2.13% after news that a 787 Dreamliner had to make an emergency landing today. This marks the third time in the past week that a 787 Dreamliner needed to land unexpectedly. We have seen the Dreamliner have problems in the past with its battery system, and now mechanical problems seem to be the issue for the planes, which when we look at the big picture shouldn't be something that weighs on investors' minds for too long.  

Walt Disney (DIS -1.67%) also fell into the red today despite what should be seen as good news from its Pixar unit. The animated film Monsters University took first place this past weekend at the box office, bringing in $82.4 million in ticket sales. It had been estimated that the film would bring in $78 million, so this was a nice surprise for the company. But Disney was still lower by 0.46% today and again similar to Boeing, investors shouldn't be discouraged by this one-day move lower. It's very plausible that the company was simply pulled lower by the overall negative sentiment moving throughout the market.  

Lastly, shares of both the Dow's banking giants also fell. Bank of America (BAC -1.55%) lost 3.07% while JPMorgan Chase (JPM 0.13%) declined by 2.00% as investors look toward China and its tightening monetary policies. Both companies have operations in Asia and will likely be hurt by what's going on in China, but investors may be overreacting today. Bank of America only realizes about 4% of its revenue from Asian markets while JPMorgan gets about 6%. In the big picture, these amounts are a drop in the bucket and really shouldn't affect the overall financial health of either company.  

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