DAX Help in Finding NEW Service

[Urvashi]

Hi

I am new to DAX and need help with the below issue. I need to find if a service is new or ongoing based on following conditions.

For DP Service - if a customer has received the same service more than once and the difference in (Next Service Start Date - Previous Service End Date) >1, then it's a 'New' service.

For HC Service - if a customer has received the same service more than once and the difference in (Next Service Start Date - Previous Service End Date )>7, then it's a 'New' service.

I need to produce result as shown below.

Customer ID	Service Type	Start Date	End Date	Rankx	Duplicate Count	RESULT
21563	DP	17/06/2019		1	2	New
21563	DP	03/04/2020		2	2	New
21563	HC	19/01/2017	06/01/2019	1	3	New
21563	HC	07/01/2019	01/04/2020	2	3
21563	HC	03/04/2020		3	3
89326	DP	21/01/2019	18/07/2019	1	2	New
89326	DP	19/07/2019	22/08/2019	2	2
89326	HC	18/06/2016	22/08/2019	1	2	New
89326	HC	05/09/2019	31/12/2019	2	2	New

Thanks in advance.

[wdx223_Daniel]

@Urvashi 

Result :=
VAR _CurrentStartDate =
    MAX ( Table2[Start Date] )
VAR _PreviousStartDate =
    CALCULATE (
        MAX ( Table2[Start Date] ),
        Table2[Start Date] < _CurrentStartDate,
        ALLEXCEPT ( Table2, Table2[Customer ID], Table2[Service Type] )
    )
VAR _PreviousEndDate =
    CALCULATE (
        MAX ( Table2[End Date] ),
        Table2[Start Date] = _PreviousStartDate,
        ALLEXCEPT ( Table2, Table2[Customer ID], Table2[Service Type] )
    )
VAR _CurrentType =
    MAX ( Table2[Service Type] )
RETURN
    IF (
        _CurrentStartDate - _PreviousEndDate
            > IF ( _CurrentType = "PD", 1, 7 ),
        "New"
    )

[MattAllington]

This is actually quite complex, but it has been solved before. I have followed this pattern and it works as advertised. https://www.daxpatterns.com/new-and-returning-customers/