Sum Previous 4 Weeks of Sales Together
I'm trying to sum our weekly sales data into 4 weeks of sales. For example, if we had $10 in sales each of the past 4 weeks, the value returnded should be $40.
I'm using this function:
WHEN WEEK('Week Beginning') > WEEK('Week Beginning') - 4
But this is just returning the sales for last week, not the aggregate of the past 4 weeks.