You can build yor crosstab using SQL at backend and get the variance too using view or stored procedure below is the sql to start with

 

Select
 SUM (CASE YEAR WHEN 'Q1-2009' THEN Inhouseunits ELSE 0 END ) AS 'Q1-2009',
 SUM (CASE YEAR WHEN 'Q1-2010' THEN Inhouseunits ELSE 0 END ) AS 'Q1-2010',
 'Variance' = SUM (CASE YEAR WHEN 'Q1-2009' THEN Inhouseunits  END )- SUM (CASE YEAR WHEN 'Q1-2010' THEN Inhouseunits  END )
FROM DBO.CROSSTAB

 

54              22                32

 

 

Cheers

Rahul