I'd say right now not as high as we might think, judging by news headlines 8000 globally? Of course about to double over the winter season.
I'm with PilotLZ, there is a certain population of pilot that will not be interested any more. And frankly many of these would become victims of recruitment age bias, especially outside of Europe. They know their career is already over. Look around you, this age group of 55+ is very significant. That's a big vacuum that will need to be filled in a few years time.