Decomposing Mortality Changes: Compression or Shifting Mortality?

Marie-Pier Bergeron-Boucher, Max Planck Odense Center
Marcus Ebeling, University of Rostock and Max Planck Institute for Demographic Research
Vladimir Canudas-Romo, Max Planck Odense Center

Shifting and compression of mortality have been studied through two components of mortality: modal age at death and variability of the age at death. These two components inform us about the timing and age patterns of mortality respectively. The aim of this study is to decompose changes in life expectancy into effects due to changes in the modal age at death and in the variability of the age at death. We introduce a new decomposition method, using recent expression of the Gompertz, and study the changes in its components. Our approach allows differentiating between the two underlying processes in mortality and their relevance to understand the dynamics of mortality. The results suggest that the increase in life expectancy, since the 1950's, is largely driven by a shift in the modal age at death.