Regulatory customs duty can be imposed by central government via notification, subject to a statutory maximum and procedural rules. Regulatory customs duty may be levied by the Central Government by notification on specified imported goods to regulate or economise imports, subject to a statutory ceiling and to different dates and rates for different goods; the duty is calculated on customs valuation and is additional to other customs duties, and Customs Act procedures, including refunds and exemptions, apply so far as practicable.