Year US Dollars, Sum Over Component Sub-periods 1980-01-01 23982330000.000000 1981-01-01 26975760000.000000 1982-01-01 22305180000.000000 1983-01-01 18320160000.000000 1984-01-01 16980130000.000002 1985-01-01 14152770000.000000 1986-01-01 11365190000.000000 1987-01-01 12396860000.000000 1988-01-01 12248670000.000000 1989-01-01 11600560000.000000 1990-01-01 10905630000.000000 1991-01-01 10406050000.000000 1992-01-01 8397620000.000001 1993-01-01 6487150000.000000 1994-01-01 6298970000.000000 1995-01-01 6656730000.000000 1996-01-01 6571210000.000000 1997-01-01 7082240000.000000 1998-01-01 6846830000.000000 1999-01-01 8954240000.000000 2000-01-01 10379970000.000000 2001-01-01 10335550000.000000 2002-01-01 9832570000.000000 2003-01-01 12555200000.000000 2004-01-01 15720950000.000000 2005-01-01 17648970000.000000 2006-01-01 20276710000.000000 2007-01-01 23882060000.000000 2008-01-01 28966980000.000000 2009-01-01 21280760000.000000 2010-01-01 22623200000.000000 2011-01-01 28130920000.000000 2012-01-01 28303890000.000000 2013-01-01 29914740000.000000