 Following Roaring Twenties growth, the Sioux City Board of Trade reincorporated as the Sioux City Grain Exchange on June 28, 1922.It relocated to the sixth floor of the Warnock Building (Benson Building today) at 705 Douglas Street in March 1928 and added a state-of-the-art cereal laboratory staffed with chemists to its inspection, grading, weighing, and storage services which operated under the license and supervision of the United States Department of Agriculture.The trading floor operated Monday through Friday, 9