Year	US Dollars
1970	31675000
1971	41577000
1972	54885000
1973	65145000
1974	94018000
1975	114510000
1976	133359000
1977	173255000
1978	609490000
1979	631712000
1980	865705000
1981	1024762000
1982	960420000
1983	972235000
1984	978445000
1985	1223454000
1986	1443385000
1987	1651862000
1988	1700350000
1989	1527923000
1990	1757442000
1991	1526039000
1992	1548655000
1993	1574539000
1994	1542267000
1995	1603275000
1996	1554444000
1997	1588605000
1998	1686516000
1999	1716417000
2000	1720694000
2001	1632891000
2002	1850780000
2003	2152688000
2004	1978802000
2005	1965761000
2006	767008000
2007	1095379000
2008	957951000
2009	1257531000
2010	1549513000
2011	2235729000
2012	2351518000
2013	2660465000
2014	2667939000
2015	2918325000
2016	3233062000