Year	US Dollars
1960	32.86189
1961	37.19839
1962	31.07971
1963	46.06925
1964	37.54576
1965	51.29738
1966	10.92906
1967	11.37885
1968	50.24362
1969	47.82138
1970	66.43539
1971	69.15358
1972	88.57215
1973	74.73551
1974	121.51506
1975	134.06029
1976	265.62632
1977	233.01626
1978	170.9677
1979	250.07818
1980	218.62804
1981	256.90484
1982	268.38914
1983	10.06829
1984	13.22471
1985	24.53696
1986	34.04932
1987	46.96787
1988	52.51916
1989	124.13067
1990	147.85975
1991	103.99513
1992	190.28845
1993	184.74104
1994	140.71101
1995	176.59786
1996	244.39318
1997	166.44328
1998	125.50109
1999	71.88739
2000	72.71429
2001	48.72854
2002	24.87562
2003	22.11283
2004	48.57297
2005	83.06536
2006	120.7418
2007	284.70714
2008	187.32511
2009	286.15504
2010	184.60665
2011	138.24242
2012	72.29744
2013	54.65053
2014	23.50434
2015	27.76836
2016	28.42878
2017	34.26039
2018	23.88351
2019	39.09705
2020	44.78927
2021	46.55905