Year metric tons 1960 2600 1961 3200 1962 2800 1963 3000 1964 3000 1965 4000 1966 4000 1967 5000 1968 6000 1969 7000 1970 8000 1971 8000 1972 8000 1973 7997 1974 8455 1975 8415 1976 8377 1977 8336 1978 8807 1979 8740 1980 8661 1981 8921 1982 8812 1983 8653 1984 6809 1985 10191 1986 9757.2 1987 10766.4 1988 10827.3 1989 9357.4 1990 10054.6 1991 3012 1992 2696.2 1993 2500 1994 2100 1995 1380.3 1996 2126.2 1997 1013.8 1998 2683.5 1999 2747.9 2000 3328 2001 3311.2 2002 3656.8 2003 2801.6 2004 4549.5 2005 5000 2006 5652.3 2007 5413.4 2008 5365 2009 5811 2010 5132.2 2011 4805.2 2012 8605.2 2013 8973.09 2014 8705.05 2015 7855.1 2016 7862.09 2017 8563.2 2018 8648.3 2019 8711.5 2020 7627.16 2021 9641.5 2022 8739.5