Attributes
Countries have 2 levels of nesting (continent > country). To reflect this, the unique IDs for each country attribute in the database is identified by a 5 character ID comprised of 2 characters for the continent and 3 characters for the country. For example the unique OEC ID for Brazil would be sabra, sa corresponding to South American and bra corresponding to the 3 character ISO code for Brazil. The diagram below explains this:
The HS (Harmonized System) comprises approximately 5,300 article/product descriptions that appear as headings and subheadings, arranged in 99 chapters, grouped in 21 sections. The six digits can be broken down into three parts (with an additional leading two devoted to the roman numeral section). The first two digits of the OEC product IDs correspond to the roman numeric sections e.g. XII (12) = Footwear and Headgear. The next two (HS-2) identify the chapter the goods are classified in, e.g. 64 = Footwear. The next two digits (HS-4) identify groupings within that chapter, e.g. 64.01 = waterproof footwear of rubber or plastic. The next two digits (HS-6) are even more specific, e.g. 64.01.10 waterproof footwear of rubber or plastic with metal capped toe. Up to the HS-6 digit level. The diagram below shows an example OEC HS92 product ID:
The Harmonized System was introduced in 1988 and has been adopted by most of the countries worldwide. It has undergone several changes in the classification of products. These changes are called revisions and entered into force in 1992, 1996, 2002, 2007, 2012 and 2017. The OEC currently uses the 1992, 1996, 2002 and 2007 revisions.