Year US Dollars, Sum Over Component Sub-periods 1980-01-01 1885000000 1981-01-01 2444000000 1982-01-01 2824000000 1983-01-01 2350000000 1984-01-01 2441000000 1985-01-01 1758000000 1986-01-01 1629000000 1987-01-01 1840000000 1988-01-01 1691000000 1989-01-01 2352000000 1990-01-01 2841000000 1991-01-01 2865000000 1992-01-01 2422000000 1993-01-01 2450000000 1994-01-01 2772000000 1995-01-01 3405000000 1996-01-01 3601000000 1997-01-01 3821000000 1998-01-01 2695000000 1999-01-01 3279000000 2000-01-01 6414000000 2001-01-01 6601000000 2002-01-01 6867000000 2003-01-01 7103000000 2004-01-01 9369000000 2005-01-01 10177000000 2006-01-01 14088000000 2007-01-01 18915000000 2008-01-01 21653000000 2009-01-01 14514000000 2010-01-01 16354000000 2011-01-01 17733000000 2012-01-01 20260000000 2013-01-01 20701000000