Calculations on report created using bip using rtf template

jameelj

I am creating my first BIP report. I am using RTF template to build this.

My question here is can I do the calculations like total revenue = income1 + income2  or net margin = income - expense on the report level rather than doing at the datamodel level.

My sample dataset query result is

Queryid     Date     Amount

income1     June     125

income2     June     75

field browser value is set to

<?for-each:G_1?><?if:QUERY_ID='income1'?><?Amount?><?end if?><?end for-each?>

Request someone to share some info on this..