Year	US Dollars, Monthly Level
1980-01-01	66887670286.4957
1981-01-01	62134400273.6004
1982-01-01	59989497426.5504
1983-01-01	58654115257.6142
1984-01-01	60391956915.0816
1985-01-01	64077684019.4287
1986-01-01	78088778801.6407
1987-01-01	93918257803.5393
1988-01-01	103897072476.3160
1989-01-01	111139356602.9570
1990-01-01	137465202789.2760
1991-01-01	137184258217.7330
1992-01-01	144885803032.3250
1993-01-01	136235107437.4740
1994-01-01	156201778930.6800
1995-01-01	191171450763.0110
1996-01-01	200608692661.7830
1997-01-01	198551073693.5570
1998-01-01	205160487918.2210
1999-01-01	205566934417.6300
2000-01-01	215934692754.0110
2001-01-01	217957499973.6690
2002-01-01	232432512802.9250
2003-01-01	276969990740.5400
2004-01-01	330058602006.6260
2005-01-01	358839198126.7270
2006-01-01	407171110411.0630
2007-01-01	472928400664.6190
2008-01-01	526135262943.7310
2009-01-01	409813571292.6480
2010-01-01	457056013189.7220
2011-01-01	537144039468.8020
2012-01-01	517539369742.0440
2013-01-01	531303902533.2910