Year	US Dollars
1970	4879000
1971	1998000
1972	3384000
1973	7914000
1974	12311000
1975	24074000
1976	47677000
1977	87493000
1978	126804000
1979	156077000
1980	189831000
1981	196580000
1982	218308000
1983	240501000
1984	290096000
1985	365596000
1986	451267000
1987	605109000
1988	653567000
1989	623297000
1990	711731000
1991	809898000
1992	857064000
1993	908962000
1994	955148000
1995	1032504000
1996	1045353000
1997	1112852000
1998	1227858000
1999	1311799000
2000	1289759000
2001	1299043000
2002	1452035000
2003	1555053000
2004	1670720000
2005	1526467000
2006	433569000
2007	619217000
2008	688908000
2009	861367000
2010	906314000
2011	1215707000
2012	1262534000
2013	1693564000
2014	2021860000
2015	2240624000
2016	2783188000