Multiplication
In a field Advanced Property:
<?ORDER_TOTAL*COMMISSION_PCT?>
Aggregation
On Grouping
<?sum (current-group()/ORDER_TOTAL)?>
Advanced
<?(sum(current-group()/ORDER_TOTAL)*COMMISSION_PCT)?>
BIP - Calculation
In a field Advanced Property:
<?ORDER_TOTAL*COMMISSION_PCT?>
<?sum (current-group()/ORDER_TOTAL)?>
<?(sum(current-group()/ORDER_TOTAL)*COMMISSION_PCT)?>