Empirical Evidence

Labys and Waddell (1989) have provided empirical confirmation of the existence of these cycles and thus of transmaterialization for some 30 commodities. To provide a more aggregate demonstration of this phenomenon, these commodities have been further aggregated into five groups, each of which represents a different cyclical period in which intensity of use has peaked and declined or has increased. The grouping of the commodities and the periods they represent have been summarized in Table 17.1. The first group consists of those materials which experienced a peak in their IOU prior to World War II. Iron ore and copper are two of the materials included. The second group consists of those materials having their IOU peak just after World War II. Examples of materials in this category include nickel and molybdenum. The third group consists of materials for which the IOU peaked during the period from 1956 to 1970, namely manganese, chromium and vanadium. The fourth group consists of materials for which IOU peaked after 1970 and includes phosphate rock, aluminum and cobalt. The fifth and final group consists of materials for which the lOU has yet to peak. This group consists of newer, lighter, more technologically intensive materials, such as the platinum group metals, titanium, plastics and advanced ceramics (Mangin et al. 1995).

To provide further but brief evidence of the cyclical character of transmaterialization, the materials intensity of use (IOU) data have been updated from the original Labys and Waddell study. Sources for the commodity consumption data include the Mineral Commodity Summaries (originally the US Bureau of Mines but now the US Geological Survey) and for GDP the Survey of Current Business (US Bureau of Economic Analysis). The summary materials group indices have accordingly been updated and appear in Figure 17.1. Beginning with the Group Index 1, those materials appeared to have experienced rapid growth until the 1920s, followed by a phase of moderate growth lasting until the 1940s, when the IOU peaked. The phase of rapid growth of the materials found in Group Index 2 began in the late 1930s and lasted until after the end of World War II. Figure 17.1, suggests that growth then continued at a moderate rate and peaked soon thereafter, decline beginning around 1955. The upswing of the materials Group Index 3, which includes the years 1934 to the mid-1950s, increases until 1957, with a definite decline beginning in the early 1960s. The consumption of the materials contained in Group Index 4 continues to increase, but at a decreasing rate, so that the IOU is declining. The growth in IOU began in the late 1940s, peaked in the early 1980s, and is now in a declining phase. The Group Index 5 features those materials currently in their rapid growth stage. This phase of their life cycle began in the 1970s and has not yet peaked.

In conclusion, the examination of longer periods of changing intensity of use suggests that dematerialization might reflect short-term changes in materials consumption patterns. But, over the longer run, the transmaterialization concept provides a more realistic view of the way changes in materials consumption are likely to occur.

Table 17.1 US materials groupings, end uses and periods of peak intensity of use

Materials

Materials included

Major end-use sector

Time span*

Peak of

groups

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