Year	2011 U.S. Dollars
1960-01-01	9841
1961-01-01	10577
1962-01-01	11158
1963-01-01	11698
1964-01-01	11927
1965-01-01	12213
1966-01-01	12844
1967-01-01	13667
1968-01-01	14469
1969-01-01	15265
1970-01-01	15991
1971-01-01	16206
1972-01-01	16709
1973-01-01	17779
1974-01-01	18634
1975-01-01	18136
1976-01-01	19332
1977-01-01	19743
1978-01-01	20310
1979-01-01	21458
1980-01-01	22148
1981-01-01	22308
1982-01-01	22384
1983-01-01	22638
1984-01-01	23363
1985-01-01	24009
1986-01-01	24695
1987-01-01	25480
1988-01-01	26536
1989-01-01	27415
1990-01-01	27954
1991-01-01	28355
1992-01-01	28563
1993-01-01	28399
1994-01-01	29045
1995-01-01	29885
1996-01-01	30232
1997-01-01	30706
1998-01-01	31075
1999-01-01	31432
2000-01-01	32661
2001-01-01	33257
2002-01-01	33305
2003-01-01	32979
2004-01-01	33255
2005-01-01	33351
2006-01-01	33900
2007-01-01	34261
2008-01-01	33612
2009-01-01	31543
2010-01-01	32050
2011-01-01	32100