I wouldn't be surprised if I didn't have 1000+ session / dance tunes stored away all in all - some are fresher in the memory, whilst others need a bit of dust blowing off of them.

The only way to tell, I guess, would be to sit down and start playing, and see how many tunes came out until I'd completely run out ... but I'd be there a while by the time I'd worked through the English and morris and Scottish and Irish and French and Scandinavian and Galician and ...