Where a specific import duty is to be applied in relation to processed products resulting from the outward processing procedure or replacement products, the amount of the import duty shall be calculated on the basis of the customs value of the processed products at the time of acceptance of the customs declaration for release for free circulation minus the statistical value of the corresponding temporary export goods at the time when they were placed under outward processing, multiplied by the amount of import duty applicable to the processed products or replacement products, divided by the customs value of the processed products or replacement products.