I think @SeniorPatzer makes an interesting question. Seconded by @isabela14. I'm 29 and i just started playing seriously about 6 months ago. The age when you start learning also plays a big role on your learning curve.
Usually if you are gifted and if your dad start to train you around 8 and with coach like Alexandra Botez,you can get to 2050 Elo in 7 years!
I went from 500-600 to 1000-1100 in 90 days.. I'm hoping on breaking 1200 soon..
I think it will take me 120 days to break 1400-1500 and about a year to become a 1700-1800 chess player! I hope in 1.5 -3 years to be around 2000!
11 months later you are 1079.