Year	2007 US$
1960	10.4
1961	22.56
1962	12.91
1963	15.24
1964	21.09
1965	25.8
1966	26.82
1967	25.37
1968	45.14
1969	53.67
1970	50.64
1971	41.17
1972	78.78
1973	60.48
1974	55.02
1975	68.69
1976	71
1977	72.27
1978	75.47
1979	84.14
1980	97.47
1981	100.9
1982	102.6
1983	131.3
1984	125.8
1985	135.9
1986	133.7
1987	139.6
1988	149.2
1989	146.2
1990	158.1
1991	175.8
1992	220.5
1993	156.3
1994	174.8
1995	165.1
1996	162.5
1997	168.8
1998	165.4
1999	186
2000	186
2001	186.8
2002	175.2
2003	207.4
2004	225.4
2005	255.6
2006	233.4
2007	221.9