Article 6 establishes the methodology for determining the value of goods subject to Excise Tax. For tobacco products, the taxable value is determined exclusively by the Supreme Council's decision from its 36th session, or any subsequent amendments. For all other Excise Goods, the value is calculated as the higher of two potential bases: either the retail sale price provided by the importer or producer, or a standard price list periodically agreed upon by the GCC Tax Administrations. This dual-valuation system ensures that the tax is levied on a comprehensive and standardised basis across Member States.