Running Total Breaks when Adding Top N

Sburi2 

I made a sample file. as you can see, I filtered by top 3, and still, the result is correct. In your initial posting of the question, you had used ALLSELECTED when you calculated the all appname total, you should use ALL. check my formula below: I attached the file as well.

Cummulative = 
var __current = [Total Sales]
var __all = CALCULATE( [Total Sales] , ALLSELECTED(financials[Product]))
var __cumm = 

    CALCULATE(
        [Total Sales],
        FILTER(
            ALLSELECTED(financials[Product]),
            [Total Sales] >= __current
        )
    )
return
DIVIDE( __cumm , __all )

Sburi2 

When you posted the question initially, I noticed that you had used ALL instead of ALLSELECTED. It was one reason for the incorrect results when you applied TOPn filter. Apart from that you also had applied some other filters. 

ar __all = CALCULATE( [Total Sales] , ALLSELECTED(financials[Product]))