Need help in DAX, a hard problem.

[srykhanna]

Can you please help how to achieve this using DAX?

Column A	Column B
10	=10
12	12 - Sum(Previous Output) = 12 - 10 = 2
13	13 - Sum(Previous Output) = 13 - (2 + 10) = 1
14	14 - Sum(Previous Output) = 14 - (1 + 2 + 10) = 1

[ryan_mayu · Accepted solution]

@srykhanna 

you can try to create an index column in PQ

then use DAX to create columns

Column = if('Table'[Index]=1,'Table'[columnA],'Table'[columnA]-maxx(FILTER('Table','Table'[Index]=EARLIER('Table'[Index])-1),'Table'[columnA]))

Column 2 = if('Table'[Index]=1,'Table'[columnA],'Table'[columnA]-sumx(FILTER('Table','Table'[Index]<EARLIER('Table'[Index])),'Table'[Column]))

pls see the attachment below