I've often wondered how long Bill Murray's character (Phil Connors) was supposed to be in his time loop before he got out of it. You could count the number of days depicted in the movie, but there are parts that reference that he had spent a much longer time between scenes not shown.
It seems that it could not have been shorter than several months, to a year at the minimum, for him to have learned may of the things that he is shown learning (like playing the Piano, Ice Sculpture and such). However, it could have been years, or decades?
Perhaps somewhere in the script, or maybe the writers of the film or director's commentary or someplace like that have given some sort of indication as to what kind of time scale they were thinking it should have been while writing/making the movie?