Year	US Dollars
1960	10.02344
1961	8.89362
1962	8.9092
1963	9.61787
1964	6.13526
1965	7.68133
1966	7.83508
1967	8.59879
1968	7.77053
1969	10.72461
1970	8.51932
1971	9.86871
1972	10.9066
1973	8.26903
1974	7.26502
1975	7.01459
1976	6.02926
1977	6.51382
1978	4.44181
1979	3.56634
1980	3.63841
1981	8.53208
1982	0.85897
1983	0.19143
1984	-0.91274
1985	-0.21615
1986	-0.42631
1987	0.25612
1988	0.22079
1989	1.21722
1990	1.21952
1991	1.25694
1992	-0.07086
1993	-0.79444
1994	-2.55883
1995	1.26405
1996	-3.27075
1997	-3.47416
1998	-1.08822
1999	-1.18198