The above evaluation methods should be used in hierarchical order. The agreement gives customs administrations the right to request additional information from importers if they have reason to doubt the accuracy of the declared value of imported goods. If, despite additional information, the administration retains reasonable doubts, it can be assumed that the customs value of the imported goods cannot be determined on the basis of the declared value and that customs should determine the value taking into account the provisions of the Agreement.  The customs value is the procedure while the customs authorities assign a monetary value to a good or service for import or export purposes. In general, the authorities are involved in this process to protect tariff concessions, collect revenue for the government agency, implement trade policy, and protect public health and safety. Tariffs and the need for customs valuation have existed for thousands of years in different cultures, with evidence of their use in the Roman Empire, Han Dynasty and Indian subcontinent. The first documented tariff dates back to 136 in Palmyra, an oasis city in the Syrian desert.  Beginning in the late 20th century, customs valuation procedures used worldwide were codified in the Agreement on Implementation of Article VII of the General Agreement on Tariffs and Trade (GATT) 1994.  The Agreement aims to establish a single system that is fair, uniform and neutral for the valuation of goods imported for customs purposes, consistent with commercial conditions and prohibits the use of arbitrary or fictitious customs values.
The Agreement recognises, by its positive view of value, that customs valuation should, as far as possible, be based on the actual price of the goods to be valued. . . .