Life expectancy at birth was low because many people died in childhood, bringing down the average. Those who survived childhood lived much longer lives. I used

Life expectancy at birth was low because many people died in childhood, bringing down the average. Those who survived childhood lived much longer lives. I used the historical list of US Supreme Court justices [0] and averaged the lifespan of the first 20 justices. The average was 67 years. Maximum was 91 [1]. [0] https://en.wikipedia.org/wiki/List_of_justices_of_the_Supreme_Court_of_the_United_States#All_justices https://en.wikipedia.org/wiki/List_of_justices_of_the_Suprem... [1] https://en.wikipedia.org/wiki/Gabriel_Duvall https://en.wikipedia.org/wiki/Gabriel_Duvall