Need current month

[#1]

Hi all,

I have this expression for straight table in which I need to subtract the value of current month, the expression is...

=

sum({<Historical_Billing.Flag={"Gross Billings"}>}Historical_Billing.MonthlyBillings) -               // this is gross billing field

sum({<Historical_Billing.Flag={"P6Data"}>}Historical_Billing.MonthlyBillings)                               //need current month for this field everytime i subtract.

the field name from were we are taking month is Historical.billing_date just in case we need it...