Hi Borislav

>Can you post some example data and desired result from it?

  date      CustomerID  DocType   debcre  ammount 
01.01.2005       0001   Invoice      +     100.00
01.02.2005       0001   Payment      -      20.00
01.03.2005       0001   Invoice      +      50.00
01.01.2006       0001   Payment      -      30.00
01.02.2006       0001   Invoice      +     100.00

....             0002
....             0003..... 
.....all Customers Movements

Result:

   Customer 0001

   date                 deb      cre    
         Last Years     150       20
01.01.2006   Payment              30
01.02.2006   Invoice    100

   Customer 0002....
                
These result can by filtered between dates and customers

João Batista