I have, conservative estimate, 500 books at home and of the total, I have re-read at least 400 of them at least once, some favorites maybe 10 times over the last 50+ years since I have been able to read (which was before I went to school -- I don't remember a time when I couldn't read and don't really know how I learned). Part of this is that I am such a voracious reader I'm always running out of books to read and can't afford to buy as many as I would like, so it's read the old ones.