Year	2007 US$
1960	45.18
1961	66.4
1962	72.98
1963	39.96
1964	47.23
1965	62.19
1966	78.69
1967	90.04
1968	93.56
1969	100.2
1970	127.6
1971	124.2
1972	146.4
1973	121.8
1974	144.1
1975	170.2
1976	194.1
1977	209
1978	205.8
1979	249.6
1980	257.5
1981	282.1
1982	278
1983	235.3
1984	275.8
1985	250.1
1986	280.7
1987	279.4
1988	285.1
1989	281.5
1990	286.5
1991	280.7
1992	279.7
1993	264.8
1994	251.9
1995	277.6
1996	288.5
1997	293.5
1998	300.5
1999	315
2000	347.3
2001	342.8
2002	327.1
2003	315.6
2004	300.8
2005	356
2006	368.9
2007	379.5