In this Dec. 21, 1999 file photo, Nicholas Torres, center, shouts an order in the eurodollar pit at the Chicago Mercantile Exchange just as the Fedeal Reserve was announcing that there would be no change in interest rates. Floor trading has shrunk to a fraction of its volume from two decades ago as faster, cheaper, computers take over the process of establishing prices on everything from pigs to Exxon Mobil's stock.