The reason why life expectancy is going down is because middle age people are dying. People dying in their 80s has almost no impact on life expectancy calculations
Isn’t life expectancy an average? If so, then reducing any input values (people dying earlier than they otherwise would) would reduce the average. Doesn’t matter in which n-tile the reductions occur.
Wouldn't a person dying 40 years early have a tenfold impact on the average compared to someone dying 4 years early. Early being compared to the expectancy calculated without them.