An Institution must number successively its customers recorded in the list giving each customer a serial number Numbering starts from No.1 and continues in column No. 1 of the list sheets and without interruption.

But if the institution deleted one of its customers due to the decrease in the total credits opened in his favour below the limit determined in the directives, or because he has ceased to become a customer of the Institution, it may never give a new customer the same serial number of the deleted one.