More than 4.5 million shares were traded, 10 times the stock's average daily volume.

These days, the daily volume is only about $20 million.

"We want the capacity to handle five times our average daily volume," he said.

This year, average daily volume has been 520 million shares.

Yesterday, 4.5 million shares changed hands compared with average daily volume of 145,600.

Almost 7.7 million shares changed hands, more than twice the average daily volume for the previous six months.

By comparison, the average daily volume for the same period in the previous three years was 25 percent lower.

A daily volume of $6 million would not give them much room to maneuver.

More than three million shares changed hands, about five times normal daily volume.

Through the week ended May 10, the average daily volume of energy contracts was up 40 percent from a year ago.