Display previous incident date for each problem (DAX)

[LFORS]

Hi all,

Im new to this forum but would love it if someone could help me with a DAX question?

What i am trying to achieve is display the date of the previous incident at a problem level. So in ITIL you can have multiple incidents with the same root cause and they are grouped at a problem level (Many:1). I have created an index in DAX that displays the sequence in which that incident occurs i.e first is 1 second is 2 etc and will reset for each problem.

Data:

Incident Number	Date	Problem	Index
INC1	1/1/2022	PRB A	1
INC2	1/2/2022	PRB A	2
INC3	1/3/2022	PRB A	3
INC4	1/4/2022	PRB B	1
INC5	1/5/2022	PRB B	2
INC6	1/6/2022	PRB B	3
INC7	1/6/2022	PRB C	1
INC8	1/7/2022	PRB D	1

Expected Result:

Incident Number	Date	Problem	Index	Previous Incident Date
INC1	1/1/2022	PRB A	1
INC2	1/2/2022	PRB A	2	1/1/2022
INC3	1/3/2022	PRB A	3	1/2/2022
INC4	1/14/2022	PRB B	1
INC5	1/15/2022	PRB B	2	1/14/2022
INC6	1/16/2022	PRB B	3	1/15/2022
INC7	1/16/2022	PRB C	1
INC8	1/17/2022	PRB D	1

I have found this post but doesnt work for what i need it to do. 

Any help would be greatly appreciated as i have been struggling with this for the past month. Thanks

[amitchandak · Accepted solution]

@LFORS , Create a new column

maxx(filter(Table, [problem] = earlier([problem]) && [date] < earlier([Date]) ) , [Date])

[LFORS]

@amitchandak Thanks so much. Worked Perfectly.