ISO 4217 or banking. At the 17th session (February 1978), the related UN/ECE Group of Experts agreed that the three-letter alphabetic codes for International Standard ISO 4217, "Codes for the representation of currencies and funds", would be suitable for use in international trade. Over time, new currencies are created and old currencies are discontinued. Frequently, these changes are due to the formation of new governments, treaties between countries standardizing on a shared currency, or revaluation of an existing currency due to excessive inflation. As a result, the list of codes must be updated from time to time. The ISO 4217 maintenance agency
Standards organization committees (TCs). These three organizations together comprise the World Standards Cooperation (WSC) alliance. ISO is composed of the national standards bodies (NSBs), one per member economy. The IEC is similarly composed of national committees, one per member economy. In some cases, the national committee to the IEC of an economy may also be the ISO member from that country or economy. ISO and IEC are private international organizations that are not established by any international treaty. Their members may be non-governmental organizations or governmental agencies, as selected by ISO and IEC (which are privately established organizations). The ITU is a