Year	US Dollars, Sum Over Component Sub-periods
1981-01-01	-3073000000
1982-01-01	-2993000000
1983-01-01	-3650000000
1984-01-01	-4061000000
1985-01-01	-3542000000
1986-01-01	-3216000000
1987-01-01	-3654000000
1988-01-01	-4092000000
1989-01-01	-4547000000
1990-01-01	-5190000000
1991-01-01	-5581000000
1992-01-01	-5664000000
1993-01-01	-4987000000
1994-01-01	-4693000000
1995-01-01	-5874000000
1996-01-01	-6008000000
1997-01-01	-6332000000
1998-01-01	-8189000000
1999-01-01	-8997000000
2000-01-01	-8443000000
2001-01-01	-6936000000
2002-01-01	-7048000000
2003-01-01	-6217000000
2004-01-01	-10917000000
2005-01-01	-12927000000
2006-01-01	-13790000000
2007-01-01	-15525000000
2008-01-01	-15155000000
2009-01-01	-15141000000
2010-01-01	-20790000000
2011-01-01	-26676000000
2012-01-01	-26799000000
2013-01-01	-27227000000