I have data about year of birth, for example 89, 76, 01, etc. First I want to make them like years - 1989, 1976, 2001, and then to structute them in intervals ( to 20; 21-30; 31-40;41-50;51-60 and after 60), I think that the years are possible to be made in the script and the intervals in a function, so the function is the problem.
