Year metric tons 1960 0 1961 0 1962 0 1963 0 1964 0 1965 0 1966 0 1967 0 1968 5 1969 15 1970 40 1971 54 1972 117 1973 180 1974 254 1975 329 1976 422 1977 515 1978 630 1979 755 1980 1150 1981 1530 1982 2100 1983 1459 1984 3275 1985 7708 1986 2706 1987 4174 1988 4958 1989 4869 1990 5226 1991 6866 1992 5504 1993 4862 1994 5903 1995 5771 1996 7724 1997 7931 1998 7175 1999 8788 2000 6596 2001 7551 2002 11532 2003 13621 2004 22114 2005 25981 2006 28393 2007 39531 2008 43120 2009 44317 2010 89021 2011 92200.35 2012 72292.85 2013 125692.89 2014 115271.42 2015 90976.46 2016 100187.15 2017 100458.36 2018 141224.38 2019 161278.62 2020 143829.72 2021 150817.59 2022 140930.63