National Statistics Country Classification

"Country is a key variable for determining a range of social and economic statistics including country of birth, country of residence, migration, international trade and balance of payments. The National Statistics Country Classification, including the definition and coding index is designed to be the standard harmonised framework used by National Statistics' users and producers involved in the collection and processing of country-related statistical data. The National Statistics Country Classification is based on ISO 3166-1, adapted to meet data needs of United Kingdom National Statistics' users and producers."