Roughly, how many millimetres will my nose droop with age?

I am 25 now, and am going to have a revision rhino. my skin is thin, and I'm Caucasian with skin that can be incredibly oily or incredibly dry. My question is, on average, by how many millimetres, in your experience, does a nose drop with age after rhinoplasty, over a lifetime? I'd love some very rough number estimates!! thank you once again Drs for your time.