Designing Crystal Report with Brought forward value

Please i am new to crystal report design even though I have been able to design some simple reports. I would appreciate your kind assistance.

I have a crystal report from VB.Net that has series of columns (fields) generated from the following two tables.

1. tblAgt - Table
fconsole (float field)
fagent
B1

2. tblDebit - Table
fmending (Date field)
ActNo
fagent
ftrans
fgrssprem (float field)
Comm
The report has the following format

Date: 01/01/2004 To 31/12/2004
Account No: 38000 To 38092

Balance bf: 00.00

fmending ActNo Fagent ftr fgrssprem Comm. Net Amt
02/02/04 38837 db001 DR 5,000.00 350.00 4,650
02/07/04 38838 db002 CR 15,000.30 200.00 15,200.30
03/02/02 29388 db003 pyt 2,000.00 100.00 1,900.00
--------------------------

The Date and the Accounts Group header were generated with the parameter fields (Range)

The Date Range (StartDate & EndDate) header
The Account Range (StartAcct & EndAcct) header

The DB or CR or Pyt entry determines whether the fgrssprm is negative or positive e.g. To get the Netamt

if ftrans = CR, then Comm is added
if ftrans = DR, then Comm is deducted

The Balance bf: is where I am having a problem with because it is suppose
to be generated from all fgrssprem that falls before StartDate eg. 1/01/2004
ie. fmending(tablefield) < startdate (parameter field)

Balance bf = sum(fgrssprem(tbldebit) is added to fconsole in table (tblagt) ie. Balance bf = fgrssprem + fconsole

I am trying to filter for all the dates that is less than startdate and to get the sum of fgrssprem is giving me 0.00 as my result.

I would be greatful if you could put me through.

Thanks

fieYou need to write a query in the Back end and design the report using that query which you should store it as Stored Procedure. What is the Database you are using?