University is often 19 or 20 here (mandatory military service!) but obviously there is no upper limit; some in my class had done it for 15 years (possibly more,

University is often 19 or 20 here (mandatory military service!) but obviously there is no upper limit; some in my class had done it for 15 years (possibly more, we had people with existing careers, but they were older than me). I was 20 and had programmed for ~12 years at the time. Obviously zero years professionally.