Which Cohort Is Currently Reaching Its Life Expectancy? Estimating and Interpreting Lagged Cohort Life Expectancy (LCLE)

Michel Guillot, University of Pennsylvania
Collin F. Payne, University of Pennsylvania

The life expectancy for the cohort currently reaching its life expectancy, or lagged cohort life expectancy (LCLE), is a mortality measure that has attracted interest in recent years, as part of the debate on mortality tempo. However, LCLE cannot be observed for the current year, because the cohort currently reaching its life expectancy is not yet extinct. Therefore the estimation of current LCLE must rely on assumptions about future mortality. In this paper, we compare various forecasting approaches for estimating the current value of LCLE in a population. We examine similarities and differences between these different approaches, and provide rules of thumb for estimating current LCLE. We also discuss the usefulness of using current LCLE as a summary measure of population health.