This report was prepared by Infrastructure Management Group, Inc., of Bethesda, Maryland and Government Finance Group, Inc., of Arlington, Virginia. The principal authors were Miriam Roskin of Infrastructure Management Group and Ann Sowder and JoAnne Carter of Government Finance Group. The authors are responsible for the accuracy of the facts and data presented herein, which derive from written materials and oral comments provided by officials of the Federal Highway Administration and relevant State departments of transportation. The contents of this report do not necessarily reflect the official policy of the Department of Transportation. This report does not constitute a standard, specification, or regulation.