The provisions of Article 91 (Calculation of Fractions of the Finalized Amount of National Tax, etc.) apply to the finalized amount of national tax calculated after the enforcement of this Act (excluding the amount of delinquent tax calculated pursuant to the provisions of Article 6, paragraph (2) of the Supplementary Provisions), and the finalized amount of national tax calculated before the enforcement of this Act is as calculated pursuant to the provisions of the former tax laws.