Year	US Dollars
1960	2.16465
1961	2.64934
1962	2.62412
1963	1.30453
1964	-0.24368
1965	-2.59141
1966	-0.41423
1967	0.3946
1968	0.11768
1969	0.74898
1970	-0.10234
1971	0.20559
1972	0.07679
1973	0.54195
1974	0.62673
1975	0.46376
1976	0.53594
1977	0.61354
1978	0.6174
1979	1.02486
1980	1.55862
1981	1.29358
1982	1.01961
1983	1.17166
1984	1.09747
1985	1.29032
1986	2.3959
1987	2.67135
1988	4.49594
1989	6.26784
1990	5.25865
1991	8.39038
1992	7.94589
1993	7.22803
1994	4.66588
1995	4.24024
1996	3.4598
1997	2.77139
1998	2.04122
1999	2.24756
2000	2.01129
2001	4.20592
2002	2.61291
2003	3.07538
2004	2.51728
2005	2.40258
2006	2.89309
2007	2.26276
2008	3.10425
2009	2.85196
2010	3.19478
2011	2.35207
2012	4.25943
2013	0.82293
2014	1.14344
2015	-0.43749
2016	0.06011
2017	-0.02656
2018	1.6456
2019	0.19782
2020	2.24124
2021	3.35154