Source: Huybrechts, M., Meersman, H., Van De Voorde, E., Van Hooydonk, E., Verbeke, A., Winkelmans, W. (2001) “Port competitiveness: an economic and legal analysis of the factors determining the competitiveness of seaports”, Editions De Boeck and Haezendonck, E. and Moeremans, B. (2019). Measuring value tonnes based on direct value added: a new weighted analysis for the port of Antwerp. Maritime Economics & Logistics, 1-13.
Several studies have attempted to measure intrinsic cargo handling values by presenting the relative added value associated with the handling of one ton of cargo. The methodologies deployed range from bottom-up to top-down approaches:
- The Port of Hamburg presented the Hamburg Rule in 1976, which became the reference standard.
- The Bremen Rule was presented in 1982 by the port of Bremen. It was based on the differences in labor costs for handling cargo and provided the following relative weights: 1 ton of general cargo equals 3 tons of dry bulk and equals 12 tons of liquid bulk.
- The Rotterdam Port Authority introduced the Rotterdam Rule in 1985 and refined the method further in 1991 with more detailed dry bulk classes.
- In 1986, the Dupuydauby Rule came with revised relative weights in cargo handling value per ton. It particularly underlines that containerization was becoming less labor-intensive, with an intrinsic value changing from 1 to 3.
- The Antwerp Rule is based on data of the Antwerp port and distinguishes thirteen traffic categories. Based on these figures, the highest added value per ton in the port of Antwerp is created by the handling of fruit. As the Antwerp Rule is only based on Antwerp data, the University of Antwerp also developed a Range rule based on data for ports in the Hamburg-Le Havre range.
- The Antwerp rule has been updated and refined in 2008 and 2015 (New Antwerp Rule). It clearly underlines the growing productivity of containerization from a labor perspective.