MPIDR Working Paper

The importance of mortality tempo-adjustment: theoretical and empirical considerations

Abstract

Bongaarts and Feeney’s papers on tempo distortions stirred the world of demographers and divided their community into tempo supporters and tempo opponents. The number of scholars following the tempo approach in fertility continues to grow, whereas tempo-adjustment in mortality still is generally rejected. This rejection is irrational in principle, as the basic idea behind the tempo approach is independent of the kind of demographic event. Whereas tempoadjustments in the TFR mainly lead to higher estimates on the hypothetical family size under current fertility conditions, this paper shows that tempo-adjustments in life expectancy can provide a very different picture of current mortality conditions compared to conventional life expectancy. An application of the Bongaarts and Feeney method to the analysis of the mortality gap between western and eastern Germany yields remarkable results: The differences in survival conditions between the two regions still are considerably higher than generally expected, and the survival gap between the two entities began to narrow some years later than trends in conventional life expectancy suggest. Since life expectancy without adjustment for tempo effects is one of the demographic tools most frequently used to analyze mortality, the conclusion is that we may need to revise our current knowledge of mortality trends and the driving factors behind them.