You can add a Festival Master that helps to analyze two year data of different time periods which helps to find some data like purchase , sales and stock particular Festival on different dates during years.

Step 1) Go to Master > Other Master > Festival Master.
Step 2) Press Add (Alt + A).
Step 3) Please Add the Festival name , Add date of festival or add Remark.
Step 4) Press Save (F2)
Step 5) After that Festival Master use in Analysis option reports.