Year	US Dollars, Sum Over Component Sub-periods
1998-01-01	4700000000
1999-01-01	5400000000
2000-01-01	6900000000
2001-01-01	9100000000
2002-01-01	13800000000
2003-01-01	18500000000
2004-01-01	24300000000
2005-01-01	27700000000
2006-01-01	31600000000
2007-01-01	42600000000
2008-01-01	52600000000
2009-01-01	42600000000
2010-01-01	49500000000
2011-01-01	55700000000
2012-01-01	51200000000