For the love of all that is good and reasonable, please, everyone, stop using the percentage of scientists becoming research faculty as a measure of PhD oversupply.
If there are too many PhDs, then there will be more scientists than there are faculty positions. This much is true.
This is not the same as saying:
Because programs are producing more PhDs than there are faculty positions, we must have an oversupply problem. This can be false.
Are “we” training too many PhDs? Maybe, maybe not. There is much more to be said on the issue. I just needed to get this out of my system until I find the time to write the rest.