Year	2011 U.S. Dollars
1960-01-01	12352
1961-01-01	12753
1962-01-01	13193
1963-01-01	13433
1964-01-01	14184
1965-01-01	14779
1966-01-01	15055
1967-01-01	14974
1968-01-01	15734
1969-01-01	16748
1970-01-01	17422
1971-01-01	17777
1972-01-01	18430
1973-01-01	19216
1974-01-01	19363
1975-01-01	19265
1976-01-01	20316
1977-01-01	21041
1978-01-01	21700
1979-01-01	22589
1980-01-01	22830
1981-01-01	22907
1982-01-01	22833
1983-01-01	23273
1984-01-01	24027
1985-01-01	24648
1986-01-01	25194
1987-01-01	25543
1988-01-01	26329
1989-01-01	27085
1990-01-01	27971
1991-01-01	30761
1992-01-01	31112
1993-01-01	30579
1994-01-01	31241
1995-01-01	31672
1996-01-01	31831
1997-01-01	32322
1998-01-01	32933
1999-01-01	33526
2000-01-01	34508
2001-01-01	34966
2002-01-01	34909
2003-01-01	34762
2004-01-01	35174
2005-01-01	35431
2006-01-01	36785
2007-01-01	38036
2008-01-01	38515
2009-01-01	36649
2010-01-01	38057
2011-01-01	39186