Year	US Dollars, Monthly Level
1960-01-01	-495376218.36910003
1961-01-01	-496423513.71389300
1962-01-01	-453581253.71992403
1963-01-01	-512854217.19239300
1964-01-01	-584509418.06769100
1965-01-01	-799529298.72295200
1966-01-01	-812266359.62660800
1967-01-01	-695300581.28114000
1968-01-01	-920050076.03137500
1969-01-01	-1052861021.41545990
1970-01-01	-1323992341.07741000
1971-01-01	-1419071615.63579000
1972-01-01	-1469120789.47446010
1973-01-01	-2063886976.60411020
1974-01-01	-2336276213.94003000
1975-01-01	-3050193608.23917000
1976-01-01	-3463803846.51941000
1977-01-01	-4082886785.35054000
1978-01-01	-4423515614.22905000
1979-01-01	-5724044609.47343000
1980-01-01	-5377545363.47124000
1981-01-01	-4517444172.28919000
1982-01-01	-5752171035.17173000
1983-01-01	-4968095359.69654000
1984-01-01	-4460020089.43396950
1985-01-01	-5451012173.20842000
1986-01-01	-5842462771.66237900
1987-01-01	-6522145141.80715900
1988-01-01	-7077544019.74764000
1989-01-01	-8661788008.32200000
1990-01-01	-11684233143.22720000
1991-01-01	-12826984693.88659900
1992-01-01	-13658645608.79630000
1993-01-01	-17139106229.14670200
1994-01-01	-14399714975.75470000
1995-01-01	-16695378925.99559800
1996-01-01	-18394432073.12810000
1997-01-01	-17196627290.54540000
1998-01-01	-20030069652.71800200
1999-01-01	-20138735016.23130000
2000-01-01	-22129583118.58680000
2001-01-01	-21606778065.55090000
2002-01-01	-24782361786.28990000
2003-01-01	-33719543962.67339700
2004-01-01	-39271945126.44630000
2005-01-01	-39248369362.99010000
2006-01-01	-45833974372.56570000
2007-01-01	-58190893915.58610500
2008-01-01	-64829451607.09680000
2009-01-01	-48828395834.51570000
2010-01-01	-40683482815.54290000
2011-01-01	-34121673201.45990000
2012-01-01	-28082809247.60540000
2013-01-01	-26201594791.05240000
2014-01-01	-27995802098.34750000
2015-01-01	-19485127259.68490200
2016-01-01	-20702955266.44920300
2017-01-01	-24169796650.37670000