Life expectancy

Life expectancy, also referred to as period life expectancy or virtual average lifespan, is the age a person would reach if the mortality rates by age remained unchanged throughout someone’s whole life. It indicates the average age reached by a newborn from that year, if progress in health care and medical knowledge would stall from that year onwards.
The actual average lifespan, i.e. the number of years a person may expect to live, is also referred to as cohort life expectancy. The disadvantage of cohort life expectancy is that it can only be calculated exactly after all persons in this cohort have died. When supplemented by forecasts, estimates on the lifespan of live cohorts would be possible, however.