Create a column that subtracts a value from the previous row until 0

[JLambs20]

I need to create the highlighted yellow column in this screenshot (Excel) but in Power BI. The column starts with a known value (story points), subtracts the points per day value, which results in a number and then that "formula" needs repeated down until the answer is 0. Help!

Thanks in advance everyone!

[jameszhang0805 · Accepted solution]

Please try the below code :

Balance = 
VAR _MaxIndex =
    MAX ( 'Table'[Index] )
VAR _Table =
    ADDCOLUMNS (
        SUMMARIZE (
            'Table',
            'Table'[Index],
            'Table'[Total Points],
            'Table'[Points/Days]
        ),
        "@Cumulative", CALCULATE ( SUM ( 'Table'[Points/Days] ), 'Table'[Index] <= _MaxIndex )
    )
VAR _ResultTable =
    ADDCOLUMNS (
        _Table,
        "@Balance",
            [Total Points] - [@Cumulative]
                + FIRSTNONBLANKVALUE ( 'Table'[Index], [Points/Days] )
    )
RETURN
    IF ( HASONEVALUE ( 'Table'[Index] ), SUMX ( _ResultTable, [@Balance] ) )