Year	US Dollars, Monthly Level
1990-01-01	17942797497.436800
1991-01-01	17731078715.877400
1992-01-01	18132138981.032200
1993-01-01	21138773203.300400
1994-01-01	25055602206.029800
1995-01-01	30669503899.886303
1996-01-01	33049659545.565296
1997-01-01	34962286591.528400
1998-01-01	33443003497.250400
1999-01-01	35678053742.823700
2000-01-01	42505114319.546005
2001-01-01	43320028067.186104
2002-01-01	50449749682.179700
2003-01-01	58962214062.641010
2004-01-01	76544997616.830000
2005-01-01	99577602722.990100
2006-01-01	121921834091.514000
2007-01-01	150336608965.626000
2008-01-01	194724887858.348020
2009-01-01	165256381792.453980
2010-01-01	226616039872.333980
2011-01-01	302563304114.900000
2012-01-01	296782052188.651000
2013-01-01	314723135433.501000
2014-01-01	322510076610.868000
2015-01-01	268079751415.042000
2016-01-01	264663426451.745030
2017-01-01	298931055024.836000