Japanâs biggest commodities exchange plans to introduce 24-hour electronic trading. The move by the Tokyo Commodities Exchange is an attempt to attract foreign investors and fend off criticism that it is slowing Tokyoâs drive to become Asiaâs leading international financial centre. The worldâs largest commodity futures exchanges, such as the New York Mercantile Exchange and the Chicago Mercantile Exchange, offer internet-based trading virtually round the clock, yet Tocom offers only five hours of trading.