Invoice or Billing documents negative or positive signs in Tables

Hi,

How can we recognise the amount signs are negative or positive(+/-) in VBRK and VBRP tables for all Invoices and Billing documents.

Is there any indicator in any other table will expain the sign when it is storing in database tables.

for example: when i create a debit memo, how the configuration settings will decide negative or positive?

Where can i find this indicators....

Is this the right place to post this question, if not please guide me....

Thanks,

Fract

Edited by: fract_get on Apr 13, 2010 5:11 PM