Year	US Dollars, Sum Over Component Sub-periods
1981-01-01	-4549000000
1982-01-01	-4358000000
1983-01-01	-3765000000
1984-01-01	-3669000000
1985-01-01	-4291000000
1986-01-01	-3412000000
1987-01-01	-3375000000
1988-01-01	-3237000000
1989-01-01	-3564000000
1990-01-01	-3568000000
1991-01-01	-3742000000
1992-01-01	-4709000000
1993-01-01	-5887000000
1994-01-01	-6619000000
1995-01-01	-8071000000
1996-01-01	-8540000000
1997-01-01	-9666000000
1998-01-01	-7609000000
1999-01-01	-7777000000
2000-01-01	-10423000000
2001-01-01	-10380000000
2002-01-01	-10382000000
2003-01-01	-12108000000
2004-01-01	-8811000000
2005-01-01	-9122000000
2006-01-01	-9874000000
2007-01-01	-11841000000
2008-01-01	-12998000000
2009-01-01	-9741000000
2010-01-01	-9323000000
2011-01-01	-10632000000
2012-01-01	-10330000000
2013-01-01	-11428000000