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 149 1993 253 1994 127 1995 100 1996 110 1997 120 1998 135 1999 150 2000 167 2001 137 2002 181 2003 158 2004 184 2005 167 2006 215 2007 225 2008 380 2009 535 2010 690 2011 843 2012 714 2013 1179 2014 1174 2015 1176.01 2016 1099.99 2017 1105 2018 1195.99 2019 1716.33 2020 1809.86 2021 2350.22 2022 2425