How to do it...

To implement this recipe, do the following:

1. Create a column in the R05_Table table using the following formula:

Net Work Duration = 
    VAR __startTime = TIMEVALUE("7:30 AM")
    VAR __endTime = TIMEVALUE("6:00 PM")
    VAR __Start = 'R05_Table'[Start]
    VAR __End = 'R05_Table'[End]
    VAR __WeekdayStart = WEEKDAY(__Start , 2)
    VAR __WeekdayEnd = WEEKDAY(__End , 2)
    VAR __NetWorkDays = 
        COUNTX(
            FILTER(
                ADDCOLUMNS(
                    CALENDAR(__Start,__End),
                    "WeekDay",
                    WEEKDAY([Date],2)
                ),
                [WeekDay]<6
            ),
            [Date]
        )
    VAR __fullDayMinutes = DATEDIFF(__startTime , __endTime , MINUTE)
    VAR __fullDays = 
        SWITCH(TRUE(),
            __WeekdayStart > 5 && __WeekdayEnd > 5 , __NetWorkDays,
            __WeekdayStart > 5 || __WeekdayEnd > 5 , __NetWorkDays - 1,
            __NetWorkDays < 2 , 0,
            __NetWorkDays - 2
        )
    VAR __fullDaysDuration = __fullDays * __fullDayMinutes 
    VAR __startDayTime = TIME( HOUR(__Start) , MINUTE(__Start) , SECOND(__Start) )
    VAR __startDayDuration = DATEDIFF(__startDayTime , __endTime , MINUTE)
    VAR __endDayTime = TIME( HOUR(__End) , MINUTE(__End) , SECOND(__End) )
    VAR __endDayDuration = DATEDIFF(__startTime , __endDayTime , MINUTE)
RETURN
    IF(
        __NetWorkDays = 1,
        DATEDIFF(__Start , __End , MINUTE),
        __fullDaysDuration + __startDayDuration + __endDayDuration
    )