Year	US Dollars
1970	11666000
1971	14812000
1972	20722000
1973	47199000
1974	54508000
1975	59301000
1976	63897000
1977	120597000
1978	103214000
1979	141677000
1980	216320000
1981	276433000
1982	302392000
1983	332406000
1984	314557000
1985	335680000
1986	339616000
1987	364679000
1988	370909000
1989	316403000
1990	318025000
1991	282094000
1992	257426000
1993	246249000
1994	196860000
1995	183415000
1996	165769000
1997	158133000
1998	140363000
1999	203849000
2000	194528000
2001	181390000
2002	211376000
2003	258130000
2004	263742000
2005	302667000
2006	365663000
2007	379282000
2008	388601000
2009	521935000
2010	570189000
2011	847365000
2012	744595000
2013	794102000
2014	866441000
2015	871282000
2016	867762000