All assessments of the additional levy will be computed on the basis of the latest business license tax paid and/or payable of record as of August 15 of each calendar year. The initial additional levy of sixty-six and two-thirds percent of the business license tax paid and/or payable of record as of August 15, 1976, will be payable in advance on January 3, 1977, for the period commencing January 1, 1977, and ending August 31, 1977, and will become delinquent if not paid by January 31, 1977; provided, however, that the assessment of sixty-six and two-thirds percent of the said business license tax may be paid in equal installments on January 3, 1977, and on April 1, 1977, and the installment due on the latter date will become delinquent if not paid by May 2, 1977. Thereafter all assessments of the one hundred percent additional levy will be due and payable in advance on September 1 of each year for the period commencing September 1 of each year and ending August 31 of the succeeding year, and will become delinquent if not paid by September 30 following the due date; provided, however, that assessments of the one hundred percent additional levy may be paid in equal installments on September 1 of the year due and payable and on March 1 of the succeeding year, and the installment due on the latter date will become delinquent if not paid by March 31. For the purpose of determining the additional charge for a new business established after August 15, the amount of the charge shall be based upon the business license fee as computed under Chapter 19 of this Code; provided, that the additional charge for new businesses commenced after August 15 shall be prorated for the balance of the additional charge period. Delinquent licensees shall be subject to the same penalties for late payment as provided in Section 19-21 of this code with respect to annual business licenses. (Ord. No. 1661 (NCS), § 4; Ord. No. 1899 (NCS), § 1.)