cumulative loss over time

Hi , mpsAutomation 

According to your description, you want to substract the  cumulative  of budget.

If this , you can refer to :
(1)This is my test data:

(2)We can create a measure like this:

Measure = 
VAR a = MIN ( 'calendar'[Date] )
VAR maxd = CALCULATE ( MAX ( 'MErged costs'[Date] ), ALL ( 'MErged costs' ) )
VAR jobN = SELECTEDVALUE( 'JobList'[Job No.] )
var _cost = CALCULATE (
            SUM ( 'MErged costs'[Cost] ),
            FILTER ( ALL ( 'calendar' ), 'calendar'[Date] <= a )
        )
var _budget = CALCULATE (
            SUM ('Budget Table'[Budget] ),
            FILTER ( ALL ( 'calendar' ), 'calendar'[Date] <= a )
        )
RETURN
    IF (
        a <= maxd,  
        _cost - _budget
    )

(3)Then we can put this measure on the visual and we can get the result like this:

If this method does not meet your needs, you can provide us with your special sample data and the desired output sample data in the form of tables, so that we can better help you solve the problem. (You can also upload you sample .pbix [without sensitive data] to the OneDrive and share with the OneDrive link to me ! )

Thank you for your time and sharing, and thank you for your support and understanding of PowerBI! 

Best Regards,

Aniya Zhang

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