Year	US Dollars, Sum Over Component Sub-periods
1980-01-01	-5984600000
1981-01-01	-5154300000
1982-01-01	-4670000000
1983-01-01	-3627400000
1984-01-01	-1785100000
1985-01-01	-1791200000
1986-01-01	3300400000
1987-01-01	7096300000
1988-01-01	11003700000
1989-01-01	3973500000
1990-01-01	-2478000000
1991-01-01	-6671000000
1992-01-01	-19100000
1993-01-01	3597500000
1994-01-01	-3361000000
1995-01-01	-4543300000
1996-01-01	-14873200000
1997-01-01	-3863800000
1998-01-01	43268200000
1999-01-01	27579400000
2000-01-01	19186600000
2001-01-01	13243900000
2002-01-01	15279600000
2003-01-01	24016500000
2004-01-01	40470400000
2005-01-01	32180700000
2006-01-01	30871800000
2007-01-01	37295800000
2008-01-01	6013100000
2009-01-01	36330600000
2010-01-01	38370400000
2011-01-01	30157500000
2012-01-01	40731600000
2013-01-01	60679600000