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9.C.4. Interpretation and application of the commodity classification. All trading countries have adopted the Harmonized System (HS) for commodity classification. Despite that significant achievement, there are differences in interpreting and applying the HS, both within the same country and among different countries. In order to reconcile trade in particular commodities, an analysis of uniformity of the HS application might be required. Differences and errors in classification normally affect only the distribution of the goods among different classes; however, they may sometimes lead to differences in total trade, which would be the case, for example, if different recording thresholds were applied to different commodities.
9.C.5. Valuation. IMTS 2010 (para 4.4) recommends that countries adopt the World Trade Organization Agreement on Customs Valuationa as the basis for valuation of their international merchandise trade for statistical purposes (whether the country is a World Trade Organization member or not) for both imports and exports. Further, it is recommended that imports be recorded on a CIF-type basis and exports on a FOB-type basis. Therefore, CIF imports would exceed the counterpart export value by the value of international insurance and freight charges even if there were no other sources of difference. Where such charges have been included, a negative adjustment is made to remove them, for comparison with FOB export values. If the actual freight charges are not known, estimates may be derived from unit value differences or through other approaches, such as the application of general CIF/FOB ratios. The determination of the customs value of imported goods is regulated by the WTO Agreement on Customs Valuation.
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