Year	US Dollars, Monthly Level
1993-01-01	11700000000
1994-01-01	14580000000
1995-01-01	19090000000
1996-01-01	19840000000
1997-01-01	23840000000
1998-01-01	28130000000
1999-01-01	30310000000
2000-01-01	38190000000
2001-01-01	40960000000
2002-01-01	48180000000
2003-01-01	72080000000
2004-01-01	104570000000
2005-01-01	143730000000
2006-01-01	182010000000
2007-01-01	245230000000
2008-01-01	292960000000