Year	US Dollars
1960	3.12708
1961	5.07829
1962	6.35782
1963	5.41155
1964	7.42909
1965	9.40267
1966	7.69966
1967	7.54955
1968	6.78117
1969	7.66348
1970	6.50429
1971	7.43117
1972	8.00799
1973	8.09472
1974	7.7445
1975	9.56034
1976	6.20979
1977	7.52147
1978	15.58912
1979	12.88492
1980	10.2307
1981	12.47313
1982	24.98059
1983	85.58142
1984	73.99673
1985	90.84372
1986	63.77796
1987	76.75935
1988	60.70044
1989	73.18283
1990	70.45034
1991	56.80966
1992	47.90876
1993	34.39565
1994	25.37579
1995	12.90004
1996	-0.05744
1997	1.00283
1998	7.79291
1999	0.88429
2000	6.39828
2001	3.52066
2002	3.21155
2003	9.55209
2004	6.05719
2005	7.55581
2006	7.27701
2007	14.5067
2008	17.13269
2009	24.67825
2010	21.87894
2011	7.59627
2012	6.00854
2013	6.84958
2014	11.26068
2015	22.73636
2016	20.3672
2017	19.87648
2018	19.7253
2019	10.98823
2020	40.67065
2021	15.10878