Year metric tons 1960 0 1961 0 1962 0 1963 0 1964 0 1965 0 1966 0 1967 0 1968 0 1969 0 1970 0 1971 0 1972 0 1973 0 1974 0 1975 0 1976 0 1977 0 1978 0 1979 0 1980 0 1981 0 1982 0 1983 17 1984 17 1985 27 1986 36 1987 48 1988 74 1989 74 1990 74 1991 74 1992 60 1993 326 1994 1068 1995 2310 1996 2504 1997 3486 1998 4790 1999 4205 2000 5435 2001 5750 2002 6089 2003 7005 2004 7880 2005 9983 2006 11220 2007 11533 2008 16078 2009 18943 2010 16972 2011 15766 2012 24351 2013 26406.9 2014 30566 2015 24536 2016 21182 2017 24899 2018 29473.4 2019 29523.3 2020 29489 2021 31005.9 2022 31568.5