I found an old list and edited/extended it a bit:
5 RRs as Hack and an average of 100.0 or lower => Amateur.
10 RRs as Amateur and an average of 80.0 or lower => Pro.
20 RRs as Pro and an average of 72.00 or lower => Tour Pro.
25 RRs as Tour Pro and an average of 67.00 or lower => Master.
40 RRs as Master and an average of 63.00 or lower =>Tour Master.
50 RRs as Tour Master and an average of 61.00 or lower => Legend.
500 RRs as Legend and an average of 60.000 or lower => Tour Legend.
200 RRs as Tour Legend and an average of 59.000 or lower => Champion.
where RRs are ranked rounds and tournament rounds,
excluding rounds on Par3 and Par5 courses.
Below Legend tier, credit wins and wins against higher tiers accelerate the promotion.