Year	US Dollars
1970	0
1971	0
1972	0
1973	0
1974	0
1975	7904000
1976	16173000
1977	25849000
1978	51399000
1979	69510000
1980	137332000
1981	149446000
1982	170158000
1983	198811000
1984	254000000
1985	319397000
1986	372966000
1987	482398000
1988	566147000
1989	595501000
1990	694508000
1991	747551000
1992	761631000
1993	786804000
1994	849543000
1995	893867000
1996	935794000
1997	921085000
1998	970399000
1999	940380000
2000	948835000
2001	903109000
2002	977942000
2003	1065436000
2004	1114790000
2005	1022676000
2006	1047370000
2007	1092303000
2008	1099285000
2009	1150022000
2010	1108949000
2011	283671000
2012	279453000
2013	277396000
2014	271385000
2015	314876000
2016	295006000