calculating column referring to a previous row from another column

[Anonymous]

Hi there,  I need help on the following task. I wand to estimate returns based on the sales data three weeks ago (*0,27) for each product. Here is an example:

i would appreciate any help on this, thanks a lot:)

[amitchandak · Accepted solution]

@Anonymous , Logic is not very clear, try a new column like

[sales] - sumx(filter(Table,[prod_nr] =earlier([prod_nr]) && [week] =earlier([week]) -3),[sales])

Can you share sample data and sample output in table format?

[Anonymous]

Thnak you so much for your fast and helpful reply:)

this works: sumx(filter(table, [prod_nr] = earlier([prod_nr]) && [week] =earlier([week]) -3),[sales]) * 0.27