Year	US Dollars, Sum Over Component Sub-periods
1980-01-01	1177000000
1981-01-01	1872000000
1982-01-01	2925000000
1983-01-01	2444000000
1984-01-01	2258000000
1985-01-01	1562000000
1986-01-01	2116000000
1987-01-01	3473000000
1988-01-01	2755000000
1989-01-01	826000000
1990-01-01	-101000000
1991-01-01	-1656000000
1992-01-01	-2496000000
1993-01-01	-1497000000
1994-01-01	-1125000000
1995-01-01	-2190000000
1996-01-01	-5564000000
1997-01-01	-2433000000
1998-01-01	1705000000
1999-01-01	-158000000
2000-01-01	-2037000000
2001-01-01	-2969000000
2002-01-01	-6442000000
2003-01-01	-5792000000
2004-01-01	-5958000000
2005-01-01	-9952000000
2006-01-01	-13332000000
2007-01-01	-11967000000
2008-01-01	-5734000000
2009-01-01	-6641000000
2010-01-01	-8626000000
2011-01-01	-5850000000
2012-01-01	5734000000
2013-01-01	5996000000