 The Organization for Economic Cooperation and Development OECD, French Organization de Cooperation et de Development Economics. OECD is an intergovernmentally economic organization with 36 member countries, founded in 1961 to stimulate economic progress and world trade. OECD is a forum of countries describing themselves as committed to democracy and the market economy, providing a platform to compare policy experiences, seeking answers to common problems, identify good practices and coordinate domestic and international policies of its members. Most OECD members are high-income economies with a very high human development index HDI and are regarded as developed countries. As of 2017, the OECD member states collectively comprised 62.2% of global nominal GDP $49.6 trillion and 42.8% of global GDP $54.2 trillion at purchasing power parity. OECD is an official United Nations observer. In 1948, the OECD originated as the Organization for European Economic Cooperation OECD led by Robert Margelin of France to help administer the Marshall Plan which was rejected by the Soviet Union and its satellite states. This would be achieved by advocating United States financial aid and implementing economic programs for the reconstruction of Europe after World War II. Similar reconstruction aid was sent to the war-torn Republic of China and post-war Korea, but not under the name Marshall Plan. In 1961, the OECD was reformed into the Organization for Economic Cooperation and Development by the Convention on the Organization for Economic Cooperation and Development and Membership was extended to non-European states. The OECD's headquarters are at the Chateau de la Nueva in Paris, France. The OECD is funded by contributions from member states at varying rates and had a total budget of 374 million euros in 2017.