I got my first folder October 1960 on my 6th birthday. Had already been using them before that. Got my first fixed blade for my own (not to just temporarily use) August 1966. It just kinda snowballed from there. I think I have around 60 or 70 folders and I'm pushing 700 fixed blades - swords, bayonets, military, hunting, fishing, specialty. That number does NOT include kitchen knives. That's a different animal and they don't really count.
ETA: also doesn't include any of the hatchets, axes or throwing knives/axes I have.