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 0 1984 0 1985 0 1986 0 1987 0 1988 0 1989 0 1990 0 1991 0 1992 0 1993 475 1994 2706 1995 3559 1996 3252 1997 1038 1998 1852.9 1999 6997.05 2000 12712 2001 8880 2002 7852 2003 6689 2004 7404 2005 4027 2006 8813 2007 2232 2008 1965 2009 3330 2010 3586 2011 2939 2012 3924.35 2013 3616.68 2014 3695.73 2015 6230.8 2016 3306.13 2017 3929.59 2018 5648.24 2019 5440.4 2020 3740 2021 1489.16 2022 1590.54