How to do this complicated data extrapolation, prediction modeling?
I am not sure I understood the problem,however if you are trying to predict sales amount my guess is ARIMA might not be the right choice as it will not consider external variables.My suggestion is to gather related features such as how did the other movie from same genre did at that time of the year in that region,weather,star presence,presence of other popular matches or tournament at that time and etc.Let me know your thoughts.