Year	US Dollars
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	11479000
1979	13762000
1980	19399000
1981	23416000
1982	28028000
1983	34345000
1984	44040000
1985	65543000
1986	76820000
1987	97513000
1988	103662000
1989	99982000
1990	120499000
1991	129466000
1992	94292000
1993	150544000
1994	154929000
1995	158741000
1996	147495000
1997	139948000
1998	154585000
1999	165886000
2000	156207000
2001	164029000
2002	180739000
2003	181239000
2004	179638000
2005	167387000
2006	174421000
2007	178329000
2008	166904000
2009	172446000
2010	230757000
2011	257503000
2012	228147000
2013	203972000
2014	187313000
2015	207463000
2016	240262000