Year	2010 U.S. Dollars
1968-01-01	14253.5250516970
1969-01-01	14541.5374021275
1970-01-01	22133.9049242035
1971-01-01	25517.1841353502
1972-01-01	29931.4707146121
1973-01-01	35393.5835661149
1974-01-01	39125.4456241907
1975-01-01	33860.3915865260
1976-01-01	37905.1189633422
1977-01-01	38557.2148870784
1978-01-01	34657.4308405071
1979-01-01	36676.5798166759
1980-01-01	36518.0450168757
1981-01-01	34979.3485018947
1982-01-01	26017.9618805561
1983-01-01	20512.7843486214
1984-01-01	18427.0047393798
1985-01-01	15734.7373699196
1986-01-01	17509.0588255314
1987-01-01	15608.7527093434
1988-01-01	16921.5486858887
1989-01-01	16194.5142988576
1990-01-01	18002.7387272615
1991-01-01	20040.4957041795
1992-01-01	20226.8542212626
1993-01-01	19413.7829327585
1994-01-01	19041.0583983076
1995-01-01	18648.8568670781
1996-01-01	18744.7805145329
1997-01-01	18588.3043453831
1998-01-01	18763.5859281919
1999-01-01	17690.9175687790
2000-01-01	18263.2300818186
2001-01-01	17585.3904549680
2002-01-01	16619.4346590337
2003-01-01	17954.9497936841
2004-01-01	18822.7300411973
2005-01-01	19309.3120670672
2006-01-01	19304.5502317946
2007-01-01	19136.1592335417
2008-01-01	19792.7203836535
2009-01-01	18861.1099983952
2010-01-01	19259.5872568465
2011-01-01	20575.4979506353
2012-01-01	21056.3471472209
2013-01-01	21005.0121226588
2014-01-01	21183.4648875212
2015-01-01	21507.9556933289
2016-01-01	21380.4527228189
2017-01-01	20796.3194603180