Once again, the stock market demonstrated just how temperamental it can get, dropping sharply to start out the week. Most news reports cited two contributing factors: a key decision about Greek sovereign debt that many expect to reach some resolution this week, and U.S. economic data showing that incomes rose but spending stayed relatively flat, pushing the savings rate up to 4%. Just before 10:30 a.m. EST, the Dow Jones Industrials (INDEX: ^DJI) were down 119 points to 12,542, while the S&P 500 (INDEX: ^GSPC) fell 14 points to 1,302.

Bank of America (NYSE: BAC) was the Dow's biggest loser, dropping more than 3% in early trading. The bank made another change in the leadership team at its investment-banking business, according to The Wall Street Journal, further highlighting the difficulties that the company has had in integrating its purchase of Merrill Lynch back in 2009. The move reportedly involves replacing a triumvirate of co-leaders at the unit, choosing one to act as sole leader going forward. With other pressure on B of A, the stock could face a tough time after its strong performance opening 2012.

Disney (NYSE: DIS) also dropped sharply, falling more than 2% in early trading. The company announced that its new Disney Fantasy passenger ship will debut in New York City in March. Whether the recent cruise-ship tragedy in the Mediterranean will have a big impact on Disney's cruise business remains to be seen, but investors will be nervous until actual cancellation figures come in.

The only stock bucking the downtrend to rise was Verizon (NYSE: VZ), up just 0.2%. Despite the small gain, the stock has fallen sharply since the beginning of the year, as its exposure to highly subsidized smartphones like the iPhone could put a crimp on margins despite boosting overall revenue.

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