Year	US Dollars
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	0
1992	79312000
1993	558987000
1994	1450018000
1995	1240357000
1996	1361321000
1997	1465765000
1998	1648136000
1999	1851042000
2000	1825516000
2001	1909486000
2002	2034422000
2003	2148631000
2004	2316620000
2005	2151259000
2006	2573388000
2007	2986951000
2008	7721514000
2009	8672797000
2010	9656499000
2011	11360381000
2012	12398446000
2013	13467329000
2014	14035070000
2015	14817264000
2016	15986792000