Year US Dollars 1970 1000571000 1971 1079130000 1972 1229411000 1973 1245693000 1974 1600895000 1975 1865319000 1976 2325634000 1977 3344454000 1978 5029136000 1979 6644776000 1980 8297077000 1981 10851628000 1982 12237902000 1983 13902415000 1984 15012833000 1985 17545477000 1986 18537201000 1987 20385277000 1988 21763489000 1989 23536744000 1990 28165123000 1991 37772316000 1992 41864437000 1993 52717187000 1994 65596256000 1995 100092688000 1996 112879505000 1997 109730683000 1998 104943986000 1999 96903111000 2000 79830059000 2001 67296714000 2002 62922123000 2003 58452978000 2004 58416706000 2005 58466721000 2006 62493472000 2007 62779005000 2008 66618743000 2009 80824069000 2010 106357875000 2011 109943316000 2012 134256717000 2013 137353246000 2014 135291566000 2015 129654081000 2016 121497197000