The above results, however, do not take into account the endogenized trend in energy intensity. The second model, estimated included a term allowing price to increase the rate of technical progress, would be expected to forecast larger reductions in emissions in the long run. Results from the two models are compared in Figures 2 and 3, for abatement in 2005 and 2030. A base-case forecast is compared with a scenario corresponding to the tax of US$3/bbl in 1995 rising to US$10/bbl in 2002, split 50/50 between energy and carbon.