Dataset:Select ProductName, right(convert(varchar(11), billdate, 106), 8) As Period, sum(sale) as TotalSale from Product Group By ProductName, right(convert(varchar(11), billdate, 106), 8)

Output:
 Product                Period                  Sale

Sugar                     Jan-08                   1000
Sugar                     Feb-08                  2000
Sugar                     Jan-09                   2000
Sugar                     Feb-09                  4000
Butter                     Jan-08                   500
Butter                      Feb-08                  300
Butter                    Jan-09                   1000
Butter                      Feb-09                  600

 How can I get the variance and % variance of last month’s figure and last year same month figures?

Desired Result:
Product                  Periods                                 Month Var Month% Var LastYr var   LastYr%Var

                         Jan-08 Jan-09 Feb-09 Feb-09

Sugar               1000    2000   2000       4000   2000          100%           1000                     100%

Thanks

Shekhar

Here's an excellent article by David Leibowitz addressing what you need:

   http://www.simple-talk.com/sql/sql-server-2005/advanced-matrix-reporting-techniques/