hello everyone,can you please explain how can i solve this problem?

[#1]

Header 1	product	sale	purchase
A	234	k	l
B	x	m	j
C	y	t	n
D	z

suppose i want to calculate x then x=234-(k+l)

and again for y  ,  y=x-(m+j)

for z, z=y-(t+n)

how can i do this?

[#2]

use Peek function in the Script.

[#3]

hi Romel

Iam using it in the script but got a problem,

Data_Details_ID is a field that Iam loading and that field i want to use in peek function can it possible?

LET vcurrent=Peek('Projected_stock_on_hand',(Data_Details_ID-2),'Data_Details')+ Peek('Projected_stock_on_hand',(Data_Details_ID-2),'Data_Details')