I am trying to find the week on week difference in revenue for all my customers. After which I want to try to find the top 10 customers in terms of growth for the last week(week 11). I have tried using this formula for the difference

zn(Sum(revenue))-zn(lookup(sum(revenue),-1) to find the difference between different weeks.

Then I am using the rank function on the difference and putting the week in filter to week 11. this doesn't seem to be working

The flow is

Auction ->product->customer-> revenue

Do you guys have any ideas as to why it is not working ???

Edit: attaching workbook

Message was edited by: Vibhanshu jain