Year US Dollars, Sum Over Component Sub-periods 1979-01-01 1285000000 1980-01-01 1406000000 1981-01-01 1382000000 1982-01-01 1487000000 1983-01-01 719000000 1984-01-01 1257000000 1985-01-01 1666000000 1986-01-01 968000000 1987-01-01 568000000 1988-01-01 770000000 1989-01-01 1310000000 1990-01-01 1158000000 1991-01-01 905000000 1992-01-01 1115000000 1993-01-01 1307000000 1994-01-01 2261000000 1995-01-01 3369000000 1996-01-01 5235000000 1997-01-01 5159000000 1998-01-01 4599000000 1999-01-01 3935000000 2000-01-01 3621000000 2001-01-01 3280000000 2002-01-01 3295000000 2003-01-01 3339000000 2004-01-01 3199000000 2005-01-01 3194000000 2006-01-01 6462000000 2007-01-01 11493000000 2008-01-01 12511000000 2009-01-01 8826000000 2010-01-01 7405000000 2011-01-01 10753000000 2012-01-01 10888000000 2013-01-01 10071000000 2014-01-01 6327000000