--------------------------------------------------------------------------------------
|Product           |        April        |        May          |        June         |
|                  |---------------------|---------------------|---------------------|
|                  | Qty  | Free |Amount | Qty  | Free |Amount | Qty  | Free |Amount |
--------------------------------------------------------------------------------------

my dbf (sales.dbf) is like this :

product c (30)
date    d
qty     n (10)
free    n (10)
amt     n(10,2)