Sum of payment amount

Hi All,

I am getting an extract from BSAK and for one payment number (AUGBL), I need to display the sum of  all amounts (WRBTR) . Right now I am doing this:

LOOP AT LT_PAYR INTO W_PAYR.

     W_OUTPUT-PaymentNumber = W_PAYR-AUGBL.

W_OUTPUT-PaymentTotal = W_PAYR-DMBTR.

w_output-discountduedate1 = W_PAYR-ZFBDT + W_PAYR-ZBD1T .

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.

.

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Append w_ouput to it_output.

ENDLOOP.

This gives me amount separately not as total.

I tried collect but didnt change anything.

Can someone advice me how to achieve this.

Thanks!