Modelling post-carriage transport costs in groupage networks

Groupage transports are frequently calculated based on freight rates assuming a declining rate with respect to volume and to transportation distance. This paper investigates the case of feeding many small shipments to customers via a freight forwarder network. It is argued that costs for post-carriage transport dominate other costs. Based on a theoretical estimate, simulation experiments for the case of a uniform distribution of customer locations around the subsidiary with a fixed shipment size per drop suggest that the aggregate costs grow progressively with increasing customer drop distances from the subsidiary. The resulting implications for transport modelling are discussed.