I have set the dates in the parameter as below, but I'm lost with the next bit... what I want is;
If @TodayDayOfWeek < 5 (so it is Monday - Thursday) then run last week's dates (from @Startoflastweek - @endoflastweek) else use this weeks date range
DECLARE @TodayDayOfWeek INT
DECLARE @EndOfThisWeek datetime
DECLARE @StartOfThisWeek datetime
DECLARE @EndOfPrevWeek DateTime
DECLARE @StartOfPrevWeek DateTime
SET @TodayDayOfWeek = datepart(dw, GetDate())
set @EndOfThisWeek = DATEADD(wk, DATEDIFF(wk,0,GETDATE()), 4)
set @StartOfThisWeek = DATEADD(wk, DATEDIFF(wk,0,GETDATE()), 0)
SET @EndOfPrevWeek = DATEADD(dd, -@TodayDayOfWeek, GetDate())
SET @StartOfPrevWeek = DATEADD(dd, -(@TodayDayOfWeek+6), GetDate())