Calculation on values on the same column

[paolomint]

Dear All,

I need to make a subtraction between two values on the same Column.

In my table I have the quantity of each ITEM at the end of the moth.

I need to add another column with the delta between two consecutive months:

quantity of February - quantity of Jannuary

quantity of March - quantity of Febrary

...

ITEM	date	Quantity	delta
V32	31.01.2021	34
V32	28.02.2021	77	43
V32	31.03.2021	30	-47
M37	31.01.2021	46
M37	28.02.2021	28	-18
M37	31.03.2021	55	27

PowerQuery using M or Dax in PowerBI is both ok.

Thanks in advance

Paolo

[V-pazhen-msft · Accepted solution]

@paolomint 

You can create a calculate column using DAX by filtering with end of previous month.

Column =

var pre_eom= ENDOFMONTH(PREVIOUSMONTH('Table'[date]))

var pre_eom_quantity = CALCULATE(SUM([Quantity]),FILTER('Table',[TEM]=EARLIER([TEM]) && [date]=pre_eom))

Return IF(ISBLANK(pre_eom_quantity),BLANK(),[Quantity]-pre_eom_quantity)

If you don't want the blank, just use: Return [Quantity]-pre_eom_quantity

Paul Zheng _ Community Support Team
If this post helps, please Accept it as the solution to help the other members find it more quickly.

[Jihwan_Kim]

Hi, @paolomint 

Please check the below picture and the sample pbix file's link down below for creating a new column.

Delta CC =
VAR currentitem = 'Table'[ITEM]
VAR rankingbydate =
RANKX ( FILTER ( 'Table', 'Table'[ITEM] = currentitem ), 'Table'[date],, ASC )
VAR previousquantity =
MAXX (
FILTER (
'Table',
'Table'[ITEM] = currentitem
&& RANKX ( FILTER ( 'Table', 'Table'[ITEM] = currentitem ), 'Table'[date],, ASC ) = rankingbydate - 1
),
'Table'[Quantity]
)
RETURN
IF ( NOT ISBLANK ( previousquantity ), 'Table'[Quantity] - previousquantity )

https://www.dropbox.com/s/7odn75hrzh0kuho/paolomint.pbix?dl=0 

Hi, My name is Jihwan Kim.

If this post helps, then please consider accept it as the solution to help other members find it faster, and give a big thumbs up.

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