NAFTA is an agreement signed by Canada, Mexico and the United States that creates a trilateral trading bloc in North America. In 2007, WTO member States accounted for 96.4 per cent of world trade and 96.7 per cent of world GDP.  Iran, followed by Algeria, is the economy with the largest GDP and trade outside the WTO, with data from 2005.   With the exception of the Holy See, observers must begin accession negotiations within five years of their admission as observers. A number of international intergovernmental organizations have also been granted observer status in WTO bodies.  12 UN member states are not officially members of the WTO. [Citation required] Explaining the role of the Asia-Pacific Economic Cooperation (APEC) in ensuring free trade The Doha Agenda also aimed to further reduce barriers to trade in services such as the economy and finance, as well as non-agricultural goods. But until 2008, negotiations failed due to differences over agricultural subsidies and a proposed “special protection mechanism” that would allow developing countries to temporarily raise tariffs to protect their farmers. Founded in 1995, the WTO, headquartered in Geneva, Switzerland, succeeds the General Agreement on Tariffs and Trade (GATT), a group created in 1948 and whose rules created the modern multilateral trading system. The WTO decision will take place at the Ministerial Conference, which is usually held every two years. .