Life expectancy refers to:-

The estimated number of years that an average person is expected to survive Total number of live births that a hypothetical woman would have if she lived through the reproductive age Difference between birth rate and death rate The number of live births per 1000 women in the child bearing age group

The estimated number of years that an average person is expected to survive

Life expectancy: This refers to the estimated number of years that an average person is expected to survive. It is calculated on the basis of data on age-specific death rates in a given area over a period of time.