What is "life expectancy" and why should you care?
Put simply, life expectancy is the average number of years a person of any given age will live. Usually, people talk about life expectancy at birth – how many years can a person born in a specific time and place expect to live? For the U.S. overall, life expectancy at birth has increased DRAMATICALLY in the last 110 years, from 1900 when it was 47 up to 78 in 2010. You can also calculate life expectancy at different ages: IF a person born in a given year lives to be 70, THEN
