If you want the customer to have an individual  invoice discount, don't change the contents of this field, but set up  terms for this invoice discount code in the Prodaja – popust racuna window.
Če želite kupcu omogočiti posamezen popust na račun, ne spremenite vsebine tega polja, vendar v oknu Prodaja – popust računa nastavite pogoje za to šifro popusta na račun.