How life expectancy varies with perturbations in age-specific mortality

BACKGROUND A naturally arising question in demography is how a given change in mortality affects life expectancy. Scholars have targeted this question with different aims and from differentperspectives. OBJECTIVE We present and prove the central relationship between change in mortality and resulting change in e0, and we systematically apply it to investigate the effect of specific mortalityperturbations. COMMENTS Expressions for the change in e_0 resulting from a change in the parameters of the standard parametric mortality model in demography, the Gompertz-Makeham model, include well-known demographic quantities, which might prove useful for future studies.