Year US Dollars, Sum Over Component Sub-periods 1980-01-01 1866000000 1981-01-01 2446000000 1982-01-01 2821000000 1983-01-01 2367000000 1984-01-01 2433000000 1985-01-01 1760000000 1986-01-01 1631000000 1987-01-01 1829000000 1988-01-01 1693000000 1989-01-01 2357000000 1990-01-01 2833000000 1991-01-01 2853000000 1992-01-01 2366000000 1993-01-01 2470000000 1994-01-01 2802000000 1995-01-01 3404000000 1996-01-01 3566000000 1997-01-01 3830000000 1998-01-01 2703000000 1999-01-01 3216000000 2000-01-01 6391000000 2001-01-01 6507000000 2002-01-01 6772000000 2003-01-01 7042000000 2004-01-01 9285000000 2005-01-01 10241000000 2006-01-01 14178000000 2007-01-01 18847000000 2008-01-01 21538000000 2009-01-01 14483000000 2010-01-01 16372000000 2011-01-01 17781000000 2012-01-01 20218000000 2013-01-01 20588000000