The decision by CME Group Inc (CME.O), announced on Wednesday, ousts traders of products ranging from grain and livestock in Chicago to gold and oil in New York. Once the only way to buy or sell a futures contract to hedge against price moves, open-outcry trading is now only 1 percent of total futures trading volume, according to the exchange operator. Options pits, which have stayed active in the face of electronic trading, will mostly remain open in both cities.