Year	2011 U.S. Dollars
1960-01-01	14733
1961-01-01	14894
1962-01-01	15642
1963-01-01	16168
1964-01-01	16894
1965-01-01	17647
1966-01-01	18472
1967-01-01	18672
1968-01-01	19284
1969-01-01	19966
1970-01-01	20286
1971-01-01	20507
1972-01-01	21375
1973-01-01	22585
1974-01-01	23094
1975-01-01	23175
1976-01-01	24061
1977-01-01	24603
1978-01-01	25323
1979-01-01	26027
1980-01-01	26250
1981-01-01	26836
1982-01-01	25761
1983-01-01	26200
1984-01-01	27463
1985-01-01	28514
1986-01-01	28916
1987-01-01	29751
1988-01-01	30828
1989-01-01	31073
1990-01-01	30668
1991-01-01	29655
1992-01-01	29563
1993-01-01	29923
1994-01-01	31019
1995-01-01	31562
1996-01-01	31740
1997-01-01	32754
1998-01-01	33814
1999-01-01	35396
2000-01-01	36903
2001-01-01	37157
2002-01-01	37836
2003-01-01	38199
2004-01-01	39020
2005-01-01	39818
2006-01-01	40526
2007-01-01	40973
2008-01-01	40773
2009-01-01	39161
2010-01-01	39951
2011-01-01	40489