Calculate difference between slicer selected values based on 15 min intervals

Hi AlexisGonzalez ,

Please check the attached PBIX file.

1. Enter Data.

Measure Table:

2. Create "Legend Table".

Legend Table = UNION(VALUES(Data[Day]),'Measure Table')

3. Create measures.

Average of Travel Time between Selected Days = AVERAGE(Data[Travel Time (min)])

Difference of Travel Time between Selected Days = 
VAR MaxDay =
    MAXX ( Data, Data[Day] )
VAR MinDay =
    MINX ( Data, Data[Day] )
VAR MaxDayValue =
    CALCULATE (
        MAX ( Data[Travel Time (min)] ),
        FILTER ( Data, Data[Day] = MaxDay )
    )
VAR MinDayValue =
    CALCULATE (
        MAX ( Data[Travel Time (min)] ),
        FILTER ( Data, Data[Day] = MinDay )
    )
RETURN
    MaxDayValue - MinDayValue

Measure = 
IF (
    MAX ( 'Legend Table'[Day] ) = "Average of Travel Time between Selected Days",
    [Average of Travel Time between Selected Days],
    IF (
        MAX ( 'Legend Table'[Day] ) = "Difference of Travel Time between Selected Days",
        [Difference of Travel Time between Selected Days],
        IF (
            VALUE ( MAX ( 'Legend Table'[Day] ) ) IN VALUES ( Data[Day] ),
            CALCULATE (
                AVERAGE ( Data[Travel Time (min)] ),
                FILTER ( Data, Data[Day] = VALUE ( MAX ( 'Legend Table'[Day] ) ) )
            )
        )
    )
)

4. Create visuals.

Best Regards,

Icey

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