Calculate Differance Between two dates, grouping by another field in data set.

Hi vincenardo 

You can try this measure to get diff between ScheduledStartDate & ScheduledCompleteDate.

diff = 
    var _min=CALCULATE(MIN('Table'[ScheduledStartDate]),ALLEXCEPT('Table','Table'[PhaseID]))
    var _max=CALCULATE(MAX('Table'[ScheduledCompleteDate]),ALLEXCEPT('Table','Table'[PhaseID]))
return 
    DATEDIFF(_min,_max,DAY)+1

and if you want to exclude weekends in the calculation, then add a calendar table, and use the measure bellow

diff = 
    var _min=CALCULATE(MIN('Table'[ScheduledStartDate]),ALLEXCEPT('Table','Table'[PhaseID]))
    var _max=CALCULATE(MAX('Table'[ScheduledCompleteDate]),ALLEXCEPT('Table','Table'[PhaseID]))
return 
    CALCULATE(COUNTROWS('Calendar'),DATESBETWEEN('Calendar'[Date],_min,_max),'Calendar'[Isweekday]<>7&&'Calendar'[Isweekday]<>1)

 result

Best Regards,

Community Support Team _Tang

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