Year US Dollars 1970 0 1971 0 1972 0 1973 0 1974 0 1975 0 1976 0 1977 0 1978 11479000 1979 13762000 1980 19399000 1981 23416000 1982 28028000 1983 34345000 1984 44040000 1985 65543000 1986 76820000 1987 97513000 1988 103662000 1989 99982000 1990 120499000 1991 129466000 1992 94292000 1993 150544000 1994 154929000 1995 158741000 1996 147495000 1997 139948000 1998 154585000 1999 165886000 2000 156207000 2001 164029000 2002 180739000 2003 181239000 2004 179638000 2005 167387000 2006 174421000 2007 178329000 2008 166904000 2009 172446000 2010 230757000 2011 257503000 2012 228147000 2013 203972000 2014 187313000 2015 207463000 2016 240262000