Date Difference in pivot Table by Dimension Values

[mrthomasshelby]

Hello,

I have a pivot table that looks like below:

Type	Start Date	End Date	diff
T1	1/9/2020	1/17/2020	-
T1	1/18/2020	1/23/2020	1
T1	1/25/2020	1/27/2020	2
T2	2/1/2020	2/4/2020	5
T2	2/6/2020	2/9/2020	2
T3	2/11/2020	2/13/2020	2

Where diff column is the difference between the Start Date of current row and End Date of the previous row, which I have used the expression =(([Start Date]) - Above(TOTAL [End Date])). But what I want is the table shown below:

Type	Start Date	End Date	diff
T1	1/9/2020	1/17/2020	-
T1	1/18/2020	1/23/2020	1
T1	1/25/2020	1/27/2020	2
T2	2/1/2020	2/4/2020	-
T2	2/6/2020	2/9/2020	2
T3	2/11/2020	2/13/2020	-

Basically I want the 'diff' column to reset each time the dimension value changes. How do I change my expression to achieve this? Thanks in advance!

@Gysbert_Wassenaar @tresesco @sunny_talwar 

[tresesco · Accepted solution]

You can just include an if clause like:

If(Type= Above(Total Type), <Your Existing exp>)

[mrthomasshelby]

Oh boy! I was trying the same thing: if(Type=Above(Type),Exp) and it wasn't working. Looks like i missed the important TOTAL parameter. Thanks a lot @tresesco ! Appreciate it.