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	0
1993	0
1994	0
1995	21822115000
1996	22027034000
1997	21598472000
1998	23313074000
1999	22960720000
2000	22235536000
2001	21108372000
2002	0
2003	0
2004	0
2005	0
2006	0
2007	0
2008	5385427000
2009	5685286000
2010	5274703000
2011	4979355000
2012	4747401000
2013	4764676000
2014	4608078000
2015	4419521000
2016	4394035000