As a measure of the years of life remaining, life expectancy decreases with age after initially rising in early childhood, but the average age to which a person is likely to live increases as they survive to successive higher ages. In the table above, the estimated modern hunter-gatherer average expectation of life at birth of 33 years (often considered an upper-bound for Paleolithic populations) equates to a life expectancy at 15 of 39 years, so that those surviving to age 15 will on average die at 54.
as a measure of the years of life remaining life expectancy decreases with age after initially rising in early childhood but the average age to which a person is likely to live increases as they survive to successive higher ages in the table above the estimated modern hunter-gatherer average expectation of life at birth of 33 years (often considered an upper-bound for paleolithic populations) equates to a life expectancy at 15 of 39 years so that those surviving to age 15 will on average die at 54