Turbo-traders take Bank of America for a ride

NEW YORK (AP) — On a normal day, 4 billion shares of stock change hands on the New York Stock Exchange. One in 10 belongs to a single company. It's not McDonald's or IBM, both of which have been on a tear.

It's Bank of America - bailed out by the government three years ago, reviled for being part of the mortgage frenzy that helped wreck the economy and selling for not much more than an ATM fee.

When the market goes up because of positive news about the economy, Bank of America stock shoots up past the stocks of other big banks. When traders get worried about Greek debt, Bank of America takes the biggest plunge.

The big swings are not driven by a fundamental bet that the bank will be more profitable because the economy is getting better or a real concern that it will lose more money than others if there is a default in Greece.

Instead, Bank of America is the stock of the moment for high-frequency trading, the supercomputer-driven buying and selling that barely existed a few years ago and now accounts for as much as two-thirds of U.S. trading.