Week over Week Change

[#1]

Hi,

I am trying to create a week over week change formula based on max week start date

I have this as the current week: sum ({<[Week Start Date]= {'$(=Max([Week Start Date]))'}>} [2015 Actual])

and I tried this as the previous week: sum ({<[Week Start Date]= {'$(=Max([Week Start Date])-7)'}>} [2015 Actual]) which is returning nothing.

I'm guessing I have the minus 7 in the wrong spot?

I would then divide the two and subtract 1 to get WoW change

[MK_QSL]

sum ({<[Week Start Date]= {'$(=Date(Max([Week Start Date])))'}>} [2015 Actual])

sum({<[Week Start Date] = {"$(=Date(Max([Week Start Date])-7))"}>}[2015 Actual])

[#3]

This is still returning nothing (only for the -7 one)