Hello Raghu,
If you want a proper reporting for Functional area then you need to create one using report painter. You can use the standard Library 0FL in transaction GRR2 for creating a report. You can create your own library as well by copying 0FL library. The table used is GLT0 (Classic GL) / FAGLFLEXT (New GL). Hope you must be using New GL functionality.
While creating a report painter there is option for functional area.
If you want to create a FSV based on functional area then you have to do configuration in OB58 and tick the Functional Area permitted then you can create the FSV using functional area.
Regards
Rohit Goel