This is not too hard to do, except for one thing. How do you define your "week"? (http://msdn.microsoft.com/en-us/library/ms174420.aspx).In your case, it looks like you are just counting weeks starting on some specific date. If so, you can specify what that start date is and then do the calculation like this:DECLARE @startDate DATE = '20120312';SELECT COALESCE(d.Week,e.Week) AS Week, Deposits, Expenditures, COALESCE(Deposits,0) - COALESCE(Expenditures,0) AS NetFROM( SELECT DATEDIFF(dd,@startDate,[Date])/7+1 AS Week, SUM(Deposit) AS Deposits FROM Table1 GROUP BY DATEDIFF(dd,@startDate,[Date])/7+1) dFULL JOIN( SELECT DATEDIFF(dd,@startDate,[Date])/7+1 AS Week, SUM(Expenditure) AS Expenditures FROM Table2 GROUP BY DATEDIFF(dd,@startDate,[Date])/7+1) e ON e.Week = d.Week;