At least in the US, that time frame is known for removing lead from gasoline and the beginning of disallowing smoking inside restaurants etc. So clearly, those harmful airborne particulates were bolstering our immune system. Without them… believe it or not, more autism.
It could also be the steady decline in the pirate population, though that’s more closely associated with the cause of global warming:
I was going to make a joke about Dihydrogen Monoxide, but this one is better.
I wonder if there’s a similar joke with something from around the timeframe of when autism diagnosis criteria changed (70s-90s)
At least in the US, that time frame is known for removing lead from gasoline and the beginning of disallowing smoking inside restaurants etc. So clearly, those harmful airborne particulates were bolstering our immune system. Without them… believe it or not, more autism.
It could also be the steady decline in the pirate population, though that’s more closely associated with the cause of global warming:
Which mangaka wrote that graph’s x axis?
https://simple.m.wikipedia.org/wiki/Mangaka
TIL