I think you missed the point of the previous commenter.
If you have 5 people who are born on the same day, 4 of which live till 80, 1 of which dies shortly after birth, the average lifespan will be 64 even though 80% of the people lived until 80.
His point was that most of our increase in average lifespan can be attributed to the reduction in infant mortality rather than people living to higher ages.
If you have 5 people who are born on the same day, 4 of which live till 80, 1 of which dies shortly after birth, the average lifespan will be 64 even though 80% of the people lived until 80.
His point was that most of our increase in average lifespan can be attributed to the reduction in infant mortality rather than people living to higher ages.