changed or not compared to the previous date

Hi bog12345,

You could create the calculated column with the formula below.

Chaging = 
VAR previous_date =
    CALCULATE (
        MAX ( 'Table'[Start of service] ),
        FILTER (
            ALLEXCEPT ( 'Table', 'Table'[ID] ),
            'Table'[Start of service] < EARLIER ( 'Table'[Start of service] )
        )
    )
VAR previous_Number =
    LOOKUPVALUE (
        'Table'[Number of Service],
        'Table'[ID], 'Table'[ID],
        'Table'[Start of service], previous_date
    )
RETURN
    IF (
        previous_Number = BLANK ()&&'Table'[ID]='Table'[ID],
        0,
        IF ( previous_Number = 'Table'[Number of Service]&&'Table'[ID]='Table'[ID], 0, 1 )
    )

Then you will get the output you expected.

Hope it can help you!:smileytongue:

Best regards，

Cherry