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 0 1994 0 1995 0 1996 0 1997 0 1998 0 1999 0 2000 0 2001 0 2002 0 2003 0 2004 0 2005 0 2006 1524.8 2007 1131 2008 1680 2009 1661.2 2010 1345.4 2011 1517.6 2012 1390.6 2013 1580.5 2014 1556.4 2015 1486.8 2016 1595 2017 1079.7 2018 1292.8 2019 1276 2020 816.45 2021 808 2022 855