How to display total in alv only for single row

Hello,

I wish to replace VAT field in my ALV OUTPUT from another ITAB using READ TABLE. But in ALV output I have multiple rows for one document number.

So the value is assigning to all the rows in output, is it possible to assign that VAT value to only one row ( to any one record from output with corresponding document number) .

Thanks in advance.

Regards,

Ritesh Inamdar