Year	US Dollars
1970	5076000
1971	5479000
1972	7363000
1973	8860000
1974	12225000
1975	13415000
1976	15429000
1977	38016000
1978	49814000
1979	81192000
1980	136799000
1981	176028000
1982	207088000
1983	211730000
1984	230292000
1985	245075000
1986	270136000
1987	326672000
1988	325156000
1989	337736000
1990	369110000
1991	383163000
1992	403396000
1993	425977000
1994	422977000
1995	426068000
1996	451987000
1997	424643000
1998	459520000
1999	471742000
2000	490098000
2001	494466000
2002	583708000
2003	643385000
2004	681058000
2005	667072000
2006	717773000
2007	700066000
2008	400955000
2009	528549000
2010	550541000
2011	513190000
2012	548458000
2013	553424000
2014	524205000
2015	526775000
2016	505448000