Source: adapted from R. Ballou (1998) Business Logistics Management, 4th Edition, Upper Saddle River, NJ: Prentice Hall.
Freight Transport Costs per Ton-Mile (in 1995 dollars)
The most important factor related to the transport cost is the amount of energy spent for each unit being moved, which is commonly related to the economies of scale that can be achieved with each transport mode. Under such circumstances maritime transportation is commonly the mode with the lowest cost per ton mile. Although air transportation has higher transport costs than road, the difference is not excessive as air cargo is usually carried over much longer distances than for road.