Regulatory customs duty may be notified on specified imported goods to regulate imports and promote economic economy under central authority. Regulatory customs duty may be imposed by Central Government notification on goods in the First Schedule to the Tariff Act (as amended) to regulate imports; the charge is limited by alternative bases of calculation-a proportion of the tariff rate specified for the goods or a proportion of the goods' value as determined under customs valuation rules-with the higher basis governing the maximum duty.