Year US Dollars 1970 103816000 1971 145537000 1972 229642000 1973 396229000 1974 528007000 1975 882648000 1976 1234274000 1977 1476400000 1978 1512806000 1979 1722579000 1980 1514019000 1981 1135599000 1982 1000630000 1983 914895000 1984 919428000 1985 1206161000 1986 1943577000 1987 2618911000 1988 2844960000 1989 3350490000 1990 3982878000 1991 4222973000 1992 3849992000 1993 3861395000 1994 4171608000 1995 4360765000 1996 4311298000 1997 4280153000 1998 4428251000 1999 4004025000 2000 3920057000 2001 3436503000 2002 3491991000 2003 3770531000 2004 4083319000 2005 3896909000 2006 4203328000 2007 4859772000 2008 2152837000 2009 2324465000 2010 2523865000 2011 2798393000 2012 2869665000 2013 4323199000 2014 4256795000 2015 5057389000 2016 5076812000