Hi,

I have transactions as below.

CustID TrxID TotalBill RcptNo RcptAmt    
000121 op001    41.5   rcp101   170      
000121 op023    21.5   rcp101   170      
000121 op046    21.5   rcp101   170      
000121 op123    21.5   rcp101   170      
000121 op137    21.5   rcp101   170      


What I want to achieve is: how to add a column called 'Balance' which mention the remaining balance.

Balance
128.5
107    
85.5
64
42.5

I have tried to create a Running Total, but it did not help since there is no 'subtract' command.