Year	US Dollars
1960	2.74154
1961	2.55329
1962	3.8339
1963	2.08946
1964	2.66713
1965	1.55862
1966	2.79641
1967	3.17912
1968	3.86887
1969	4.35985
1970	5.0517
1971	6.05237
1972	7.19715
1973	7.52076
1974	10.20483
1975	12.66126
1976	11.43338
1977	12.13008
1978	18.29723
1979	22.80155
1980	26.88487
1981	26.86638
1982	27.24742
1983	29.11453
1984	28.43089
1985	27.72016
1986	37.94549
1987	38.12113
1988	38.03226
1989	38.37954
1990	47.87744
1991	45.82804
1992	53.85259
1993	39.05336
1994	55.69052
1995	48.36685
1996	18.63584
1997	9.52082
1998	11.39124
1999	12.15175
2000	14.79313
2001	21.53663
2002	25.85526
2003	33.17375
2004	50.39256
2005	49.47709
2006	56.41281
2007	63.50847
2008	62.86822
2009	66.10699
2010	68.76708
2011	60.51778
2012	53.51142
2013	55.05944
2014	49.10951
2015	34.20481
2016	68.11132
2017	39.0674
2018	39.27621
2019	46.66758
2020	39.38306
2021	47.04167