Comparing the two models, it can be seen that endogenizing the trend does in most cases imply a greater potential level of carbon abatement. The models are broadly similar in 2005 but the difference becomes greater in the longer term. As the tax level reaches its maximum in 2002, for the error correction model there is little difference between the abatement level in 2005 and 2030, apart from some longer term adjustment to the higher price level. For the endogenous model however, the
intervening 25 years at the high price level brings about continued reductions in energy intensity.