Subtract current row value from previous row value

Hi everyone,

I have a report that shows the summary of sales by day 1 and this can be filtered by other values like the sales rep, region and week number.

However, I want to present my data so that it will show the difference between the previous day sales and the current day.

Please note there is no date field in the table, just Day number and week number.

for the week slicer: we have values like

- Week 1, Week 2, Week 3, etc.