At the end of each reporting period, a journal voucher shall be prepared charging the various operating expense accounts and crediting account 2119, Sundry Accounts Payable, with the total amount of the unpaid bills and invoices on hand. The journal voucher shall have sufficient detail to permit identification of the bills being recorded (i.e., name of vendor, description, and amount). At the beginning of the subsequent month this entry shall be reversed. When payment is effected, the charge to the respective expense accounts will be made.