 When trade orders and information began to be communicated by telegraph, Morse code operators were employed, later replaced by phone operators.In the late 20th century, electric display boards lined the walls of the trading hall and the advent of electronic trading resulted in computers being placed on desktops.Subsequent additions to the Board of Trade Building moved the agricultural and financial trading floors out of the original trading room and into new spaces in the additions to the building's rear in the 1980s.