INTERSECT in time series

[RC0619]

Hi,

I am using INTERSECT function to capture the volume of different categories being added in different months. However, I am struggling to get rid of the very first column which is the earliest date. Any advice, please?

My measure is as follows: 

addition =

VAR TM = VALUES('Table'[Category])

VAR LM = CALCULATETABLE(VALUES('Table'[Category]),DATEADD('Table'[Date],-1,MONTH))

RETURN SUMX(EXCEPT(TM,LM),SUM('Table'[Volume]))



My raw data:

Date	Category	Volume
2021-01-01	A	2
2021-02-01	A	4
2021-03-01	A	5
2021-04-01	A	1
2021-01-01	B	3
2021-02-01	B	2
2021-03-01	B	5
2021-03-01	C	2

[lbendlin · Accepted solution]

addition = 
VAR TM = VALUES('Table'[Category])
VAR LM = CALCULATETABLE(VALUES('Table'[Category]),DATEADD('Table'[Date],-1,MONTH))
VAR md = CALCULATE(min('Table'[Date]),aLL('Table'))
RETURN if (md=max('Table'[Date]),BLANK(),SUMX(EXCEPT(TM,LM),SUM('Table'[Volume])))