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 5 1972 10 1973 25 1974 40 1975 80 1976 51 1977 102 1978 305 1979 100 1980 222 1981 445 1982 360 1983 390 1984 513 1985 1620 1986 2520 1987 4523 1988 5260 1989 8131 1990 13076 1991 18283 1992 19098 1993 18752 1994 15332 1995 8611 1996 17584 1997 22538 1998 20436 1999 42544 2000 34823 2001 49167 2002 56102 2003 62746 2004 46077 2005 23455 2006 18574 2007 30699 2008 46673 2009 59295 2010 47575 2011 60473 2012 76564 2013 75909 2014 86454 2015 80622 2016 83333 2017 86866 2018 78975 2019 95085 2020 89055 2021 115760 2022 108745