The majority of baled cotton has traditionally moved by rail from warehouse locations to ports and mills within the United States. Over the last two decades, motor carriers have greatly increased their share of cotton traffic on both short- arid long-distance movements. With passage of the Staggers Rail Act of 1980, railroads are allowed greater freedom to price their services and, through contracts, to offer specific service levels in exchange for guaranteed volume commitments by shippers. In order that each mode may be utilized in services for which the greatest comparative advantage exists, shippers, railroads, and motor carriers are encouraged to adopt costing methodologies which consider both transport and nontransport costs of cotton shipments.