Universiteit Leiden

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The Weight of Nations

Material outflows from industrial economies.

1999  -   2000
Ester van der Voet
Ministry of Housing, Spatial Planning and the Environment (VROM)


In 1997, the WRI launched the publication "Resource Flows: the material basis of industrial economies". In this publication, four countries - Germany, the USA, Japan, and the Netherlands - are compared regarding the total inflow of materials into their economies in kg/year. Not only the Direct Material Input (DMI) was recorded, but also the Total Material Requirement (TMR), over a period of 30 years. The TMR includes the hidden flows, i.e. the resources extracted on behalf of, but no longer visible in, the finished products. DMI and TMR are presented as indicators for environmental pressure to be used on a national level. The current project aimes at a follow-up WRI publication concentrating on the outflows out of the economy to the environment: the DMO or Domestic Material Output. The DMO contains emissions and final waste as well as and the domestic hidden flows. By adding an account of the outflows two purposes are fulfilled: (1) a complete balance for the national economies emerges, also enabling to detect stockbuilding in the economic system, and (2) a check is provided on the relevancy of the DMI/TMR as a measure for environmental pressure. The group of four countries is expanded to five by adding Austria. CML is responsible for the Dutch contribution to this international project.

More information

Matthews, E., C. Amann, S. Bringezu, M. Fischer-Kowalski, W. Hüttler, R. Kleijn, Y. Moriguchi, C. Ottke, E. Rodenburg, D. Rogich, H. Schandl, H. Schütz, E. van der Voet, H. Weisz  The weight of nations. Material outflows from industrial economies World Resources Institute, Washington, DC, 125 p., 2000, ISBN: 1-56973-439-9.