Year	US Dollars
1961	-0.47101
1962	-6.55755
1963	-2.40194
1964	-1.88943
1965	-2.49105
1966	-2.54659
1967	-2.31794
1968	0.01468
1969	0.44412
1970	0.43598
1971	0.5939
1972	0.64567
1973	0.40184
1974	0.36878
1975	0.3011
1976	0.16256
1977	0.40891
1978	0.70726
1979	0.82846
1980	6.86137
1981	5.97574
1982	3.54524
1983	2.9723
1984	2.46419
1985	2.22872
1986	2.52021
1987	1.65489
1988	2.78984
1989	2.13573
1990	7.6779
1991	8.7794
1992	4.02929
1993	1.22759
1994	2.72377
1995	2.55555