Year	2011 U.S. Dollars
1960-01-01	6109
1961-01-01	6772
1962-01-01	7285
1963-01-01	7846
1964-01-01	8633
1965-01-01	9022
1966-01-01	9862
1967-01-01	10840
1968-01-01	11995
1969-01-01	13274
1970-01-01	14471
1971-01-01	14909
1972-01-01	15941
1973-01-01	16983
1974-01-01	16549
1975-01-01	16848
1976-01-01	17330
1977-01-01	17918
1978-01-01	18692
1979-01-01	19551
1980-01-01	19943
1981-01-01	20625
1982-01-01	21172
1983-01-01	21672
1984-01-01	22492
1985-01-01	23768
1986-01-01	24312
1987-01-01	25188
1988-01-01	26873
1989-01-01	28208
1990-01-01	29679
1991-01-01	30549
1992-01-01	30683
1993-01-01	30638
1994-01-01	30819
1995-01-01	31340
1996-01-01	32083
1997-01-01	32518
1998-01-01	31789
1999-01-01	31669
2000-01-01	32322
2001-01-01	32346
2002-01-01	32382
2003-01-01	32876
2004-01-01	33621
2005-01-01	34056
2006-01-01	34634
2007-01-01	35392
2008-01-01	35040
2009-01-01	33144
2010-01-01	34519
2011-01-01	34294