Webi report previous year values

Hi all,

we have webi report.which displays actual and budget fisalyear period values for given fiscal year in each actual and budget crosstabs..

now i need to enhance the webi report that should display two more crosstabs which display the previous year budget and actual values for the given input fiscal year.

i have created but it display null values.

i used the below formulae.

= [Actual] where ([FiscalYear]=[fiscal Year-1] )

= [Budget] where ([FiscalYear]=[fiscal Year-1] )

Thanks in Advance.

HP