The economic impact of the port sector is usually measured at an aggregate level This paper attempts for the first time to calculate it at a disaggregate level, by identifying, quantifying and locating relations between the various port actors themselves and between them and the rest of the Belgian economy. The main goal of this analysis is to obtain a better estimate of the economic impact sizeable events may have onto the port area, such as the loss of traffics or the development of new maritime connections. Considering the importance of the ports for the Belgian economy, this research is necessary, not only for the port perimeter but beyond its boundaries, as highlighted by the geographical analysis.

A so-called bottom-up approach was used for the port of Antwerp, in order to construct a regional inputoutput table based on microeconomic data for the year 2000. In so doing, major suppliers and customers of the port's key players could be identified. A regional analysis was conducted, on the basis of the same disaggregate data, highlighting the geographical ties, alongside the functional ties, that link those various economic branches together.

The main tools used for the sectoral analysis are technical coefficients, the linkages and external input and demand indices. For the geographical analysis, the "geocoding" technique was used to map and locate all activity.

The technical coefficients measure the first-level relations between sectors with supplier-customer ties. The linkages concern the total impact (infinite level) a port actor has on its suppliers or customers. Together, these measurements lead to the conclusion that freight forwarders play a key role in the port economy. They are indeed the Antwerp port actors' first customer and exert a major influence on some of their suppliers, such as the agents, the terminal operators and the shipping companies. The way these various actors are intertwined was sketched and quantified. Some very close relations, like those linking the forwarders to the agents or to the terminal operators, can be explained by co-operation agreements, dedicated terminals, strategic alliances and, increasingly, by mergers. In a second part, the relations between the Antwerp port actors and the rest of the Belgian economy are clarified. The oil sector, quite expectedly, seems to be a crucial one, both inside and outside the Antwerp port area. The fuel trade plays a major part as Belgian customer of the Antwerp port businesses, while hinterland transport companies constitute their main supplier.

According to the postcodes of the companies surveyed, most customers and suppliers of Antwerp port actors are based in the province of Antwerp, which tends to confirm the existence of agglomeration effects.
Moreover, the main locations for the port of Antwerp’s customers and suppliers, namely, the city of Antwerp, the Brussels region and the other Belgian seaports, happen to be most easily accessible by road, rail and inland waterway. Besides, the year 2000 data show how dominant the position of the Scheldt's right bank is in Antwerp, by far outstripping the left bank, in terms of both concentration of port operations and concentration of suppliers and customers.

As mentioned before, the coefficients calculated and the relations emphasized in the framework of this study can be used to outline the potential effects that changes in Antwerp port activity might have on port actors as a whole and on the rest of the Belgian economy. Generally speaking, a similar methodology can be used for the same sort of sectoral research: other ports, transport sector, manufacturing industries, etc.