Year US Dollars 1970 5984158000 1971 7726268000 1972 11863652000 1973 15066010000 1974 22464944000 1975 27781562000 1976 33801314000 1977 42500190000 1978 55032105000 1979 61795267000 1980 71983914000 1981 81914151000 1982 94428715000 1983 99022192000 1984 104364920000 1985 104173243000 1986 109645175000 1987 120476588000 1988 118039403000 1989 114930117000 1990 120311880000 1991 121336721000 1992 129535946000 1993 144599584000 1994 152903119000 1995 160964216000 1996 181793533000 1997 198980295000 1998 241998416000 1999 245114974000 2000 242511682000 2001 229959721000 2002 231944172000 2003 235907976000 2004 220693598000 2005 188364548000 2006 194303020000 2007 238444455000 2008 262957242000 2009 281651132000 2010 352364412000 2011 404046105000 2012 440514543000 2013 483765356000 2014 556920799000 2015 543397349000 2016 543257252000