Year US Dollars, Sum Over Component Sub-periods 1981-01-01 6806000000 1982-01-01 1893000000 1983-01-01 963000000 1984-01-01 5707000000 1985-01-01 5822000000 1986-01-01 2458000000 1987-01-01 4674000000 1988-01-01 5678000000 1989-01-01 6664000000 1990-01-01 5352000000 1991-01-01 4801000000 1992-01-01 7022000000 1993-01-01 8231000000 1994-01-01 7901000000 1995-01-01 6533000000 1996-01-01 5948000000 1997-01-01 10075000000 1998-01-01 18428830000 1999-01-01 20643430000 2000-01-01 25042010000 2001-01-01 22696090000 2002-01-01 23513240000 2003-01-01 24563070000 2004-01-01 20151800000 2005-01-01 17533560000 2006-01-01 29659960000 2007-01-01 32754140000 2008-01-01 22916000000 2009-01-01 30931000000 2010-01-01 30627000000 2011-01-01 34783000000 2012-01-01 8619000000 2013-01-01 6150000000