The Combined Nomenclature (CN) is a tool for classifying goods, set up to meet the requirements of the Common Customs Tariff and the EU's external trade statistics. It forms the basis for the declaration of goods; at importation or exportation or when subject to intra-Union trade statistics. This determines which rate of customs duty applies and how the goods are treated for statistical purposes. Other legislation may also refer to the Combined Nomenclature. The CN is thus a vital working tool for business and the Member States' customs administrations. The Combined Nomenclature was established by Council Regulation (EEC) No 2658/87 on the tariff and statistical nomenclature and is updated every year.