By the way, one thing you should do when filtering for a date range is to use the following pattern, where the start has a greater-than-or-equal to clause and the end has a strictly less than clause, but moved up by one day. In your case it would be
WHERE
DateColumn >= dateadd(dd,datediff(dd,0,getdate())/7*7-7,0)
AND DateColumn < dateadd(dd,datediff(dd,0,getdate())/7*7,0)