The active life expectancy represents the average duration of activity, in years, of a generation that would be subject to the activity conditions observed over the current period.
It is calculated as the sum of the activity rates at each age from a given initial age (for example, for the "active life expectancy at 50", the sum of the activity rates at 50, 51, 52 etc. observed over the current period). It is independent of the demographic structure. This indicator is described as “apparent”, as it takes no account of deaths that may occur during the activity period, nor of changes that could affect activity behaviour by age in the years to come.