Ticking away
The moments that make up a dull day
You fritter and waste the hours
In an offhand way
Kicking around on a piece of ground
In your hometown
Waiting for someone
Or something to show you the way
Tired of lying in the sunshine
Staying home to watch the rain
You are young and life is long
And there is time to kill today
And then one day you find
Ten years have got behind you
No one told you when to run
You missed the starting gun
That's the baby boom moving up the chart. It's 1980, they're 15-35. You can clearly see the normal population before the baby boom and it's fall off.
Yes, exactly my point. The boomer generation itself made the population pyramid look different at every stage of its life, which is why the 1980 chart looks so different from the 2023 chart. When you introduce a cohort that has its own slope from birth statistics, the shape of the drop off at 60 is confounded by the preexisting shape of the slope before they entered old age.
So the appropriate method of isolating the variable that shows what you call a "die off" would be to just pull up the actuarial tables that show what percentage of 60, 61, 62 year olds, etc., die that year. Not to compare how many of those there are as a percent of overall population.