Year metric tons 1960 8300 1961 8600 1962 9100 1963 9600 1964 12000 1965 15900 1966 16200 1967 16200 1968 14600 1969 14400 1970 17200 1971 19100 1972 14800 1973 4700 1974 5900 1975 3930 1976 2970 1977 2472 1978 2515 1979 2800 1980 3507 1981 3828 1982 3750 1983 3900 1984 4300 1985 4000 1986 4100 1987 4000 1988 4067 1989 4269 1990 4981 1991 4262 1992 4607 1993 4203 1994 5318 1995 6380 1996 8808 1997 10394 1998 14014 1999 15873 2000 15696 2001 15405 2002 12315 2003 9228 2004 10030 2005 9475 2006 9915 2007 13279 2008 16795 2009 17072 2010 18083 2011 24066 2012 28759 2013 38416.3 2014 50204.5 2015 50579.5 2016 50516.24 2017 56127.1 2018 63885.77 2019 59430.89 2020 60536 2021 73880 2022 102470