In 2007 the International Institute for Strategic Studies estimated Iran's defense budget at $7.31 billion, equivalent to 2.6% of GDP or $102 per capita, ranking it 25th internationally. The country's defense industry manufactures many types of arms and equipment. Since 1992, Iran's Defense Industries Organization (DIO) has produced its own tanks, armored personnel carriers, guided missiles, radar systems, a guided missile destroyer, military vessels, submarines and a fighter plane. In 2006 Iran exported weapons to 57 countries, including NATO members, and exports reached $100 million. It has also developed a sophisticated mobile air defense system dubbed as Bavar 373.