Commodity Freight and Trip Generation by Logistics Distribution Centers Based on Sectorial Employment Data

This paper outlines and applies a method to estimate freight flow generation and trip generation, with the emphasis on distribution facilities at the regional level. Freight movements are not limited to direct shipments of goods from production locations or major ports to the points of rework or consumption. Distribution facilities generate freight flows themselves, functioning as nodes in supply chain networks. The forecasting of regional freight flows has to overcome some rather serious data shortages. In general, the published statistics do not provide information on underlying transport purpose, while the purpose of transport movement is a crucial variable for the estimation of flow volume and the number of trips. The paper shows that the observed road cargo flow, generated by distribution facilities, is strongly correlated with the employment level in some sectors of the economy. Using transport statistics with extra information on transport purpose, we have found that distribution facilities’ freight and trip generation are proportional to the number of employees in some specific economy sectors. The estimation method has been applied at the aggregate commodity flow level and at the level of a single commodity. The added value of the paper is that it shows validity of this simple estimation method. We also define the sector selection criteria for the distribution-related flow and trips. The method allows estimation of the flow and trips generated by distribution facilities for the regions where the data on transport purpose is not available.