Year	US Dollars
1960	0.14831
1961	0.28822
1962	0.98056
1963	0.68082
1964	0.79424
1965	6.43617
1966	7.64469
1967	16.15173
1968	18.93803
1969	6.94142
1970	15.60982
1971	8.07699
1972	13.10557
1973	14.78849
1974	32.60621
1975	34.66093
1976	43.40451
1977	67.60775
1978	90.30729
1979	235.0113
1980	155.82992
1981	178.2211
1982	177.44582
1983	176.94187
1984	150.5844
1985	131.16274
1986	144.21393
1987	211.10563
1988	176.23215
1989	231.85842
1990	275.00076
1991	172.50783
1992	222.2446
1993	285.65111
1994	294.0911
1995	320.47372
1996	292.62937
1997	255.02196
1998	198.23767
1999	189.44519
2000	160.03431
2001	199.98062
2002	173.50006
2003	213.19797
2004	193.36227
2005	311.36103
2006	212.44938
2007	300.2682
2008	239.77855
2009	343.92965
2010	617.60241
2011	822.96417
2012	727.24229
2013	757.2206
2014	753.38099
2015	644.5412
2016	781.49981
2017	827.49138
2018	926.77125
2019	1028.57521
2020	1547.58963
2021	1066.52706