Thanks. Previous function does not work.
As I said,
Running Sales 2016 = Last(RunningSum(([Total Sales]);([Fiscal Year])))) which works fine.
I have issue with "Running Sales 2015" for which I used the below formula as you said.
Running Sales 2015 =Previous(RunningSum([Total Sales for FI] Where ([Year of PA Fiscal Year/Period]=[PrevYear1]))) . This does not work. If I hardcode the value ' 2015' instead of the variable 'PrevYear1' it works fine. The variable - PrevYear1 = ([Year of PA Fiscal Year/Period]-1) which returns 2015,2014...and so on.
Pls let me know if there is any mistake I am doing. This is really very urgent.