Unbelievably Good News
By Bryan Caplan
I wish Julian Simon were around to read this passage from “The Low-Fertility Trap Hypothesis: Forces that May Lead to Further Postponement and Fewer Births in Europe”:
In the past decades, population projections were based on the expectation that after the end of the demographic transition, life expectancy would reach a certain maximum level… The United Nations population projections give the longest series of consistent projections for all countries in the world and serve as a model for a large number of national population projections. Until very recently, they have assumed that there is a maximum life expectancy that no country in the world will surpass. In the 1973 assessment, this maximum life expectancy was assumed to be 72.6 years for men and 77.5 years for women (Bucht 1996). As time passed, many countries came close to or even passed this assumed maximum life expectancy. As a consequence, the UN has been slowly moving the assumed maximum life expectancy upwards. In the 1982 assessment of the UN projections, the maximum age was assumed to be 75 years for men and 82.5 years for women. Only 20 years after this assumption was made, a large number of countries had again already surpassed the assumed maximum age and the trend in increasing life expectancy shows no sign of levelling off. In fact, the trend in the countries with the world’s highest life expectancy at any point in time shows an almost perfectly linear trend for more than a century with no sign of levelling off (Oeppen and Vaupel 2002). As a consequence, in their most recent population projections, the UN has given up the assumption of a maximum life expectancy and assumes continuing improvements, although at a decelerating speed (UN 2004).
I can’t remember the last time anything was better than my maximum estimate. I wonder how the U.N. statisticians felt to see their maxima exceeded twice. Happy that the world was so wonderful, or depressed that their insight was so poor?