The CBOT invented standardized futures trading to solve a grain problem: farmers and merchants needed a way to fix prices before harvest. Its grain contracts still use the 5,000-bushel unit and quarter-cent tick from the nineteenth century.
It later became the home of US treasury-futures, so today the same division prices both corn and the long bond.
Example: corn-futures, wheat-futures, soybean-futures, zb and zn are all CBOT products, cleared alongside CME's index futures at one clearing house.
Related: cme-group, treasury-futures, pit-trading