Calculate Difference Between Rows (Row Data is a Measure, Not a Calc Column)

Hi, samdep 

Please check the below picture and the link down below (sample pbix file) whether it is what you are looking for.

The measure is in the sample pbix file.

Diff qty count =
VAR currentnumber =
MAX ( 'Table'[Day Calc Column] )
VAR onerowbefore =
CALCULATE (
MAX ( 'Table'[Day Calc Column] ),
FILTER ( ALL ( 'Table' ), 'Table'[Day Calc Column] < currentnumber )
)
VAR onerowbeforeqty =
CALCULATE ( [total qty], 'Table'[Day Calc Column] = onerowbefore )
RETURN
IF ( NOT ISBLANK ( onerowbeforeqty ), [total qty] - onerowbeforeqty, BLANK () )

https://www.dropbox.com/s/afahpn09tch8lii/samdep.pbix?dl=0 

Hi, My name is Jihwan Kim.

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