Year	US Dollars
1960	11.81023
1961	8.74373
1962	9.68829
1963	15.08189
1964	8.58068
1965	25.01228
1966	14.67646
1967	12.15609
1968	9.00678
1969	11.1943
1970	10.40109
1971	12.50744
1972	7.98679
1973	13.61003
1974	9.44001
1975	12.81936
1976	16.58763
1977	13.26827
1978	11.14436
1979	10.38281
1980	12.43238
1981	12.13624
1982	13.84711
1983	15.22993
1984	28.99547
1985	22.36165
1986	15.77687
1987	16.59824
1988	9.6728
1989	8.33425
1990	40.70666
1991	44.6395
1992	77.14978
1993	30.95303
1994	14.45488
1995	17.13875
1996	20.93371
1997	19.42368
1998	11.11197
1999	8.27353
2000	8.97815
2001	11.37528
2002	9.54184
2003	11.48476
2004	9.54888
2005	8.60288
2006	11.5212
2007	-37.20407
2008	10.1394
2009	18.69727
2010	35.76813
2011	30.07585
2012	13.6756
2013	2.41001
2014	-49.69665
2015	2.59028
2016	5.61553
2017	10.19271
2018	9.39678
2019	16.6567
2020	33.71138
2021	20.80084