nearly 15 for me, started when I was 9 had a bit of a break when I was in university I would still ride when I came home but it was only every few months
Get ready... THREE! Three whole years. 5 if you count the two my sister used to work on a livery yard when I was about 10/11 and I used to go up and visit/help with stuff.
I think I should get a prize for being the least experienced