Year metric tons 1960 12200 1961 12200 1962 13100 1963 15200 1964 15200 1965 15800 1966 15300 1967 15400 1968 15800 1969 16500 1970 15628 1971 30668 1972 27271 1973 45600 1974 50027 1975 34774 1976 50671 1977 27555 1978 52224 1979 34488 1980 44620 1981 46509 1982 17589 1983 15387 1984 17663 1985 25921 1986 25815 1987 26072 1988 26526 1989 26098 1990 26562 1991 26101 1992 26541 1993 25951.69 1994 26466.31 1995 39444.66 1996 38047.45 1997 46505.43 1998 78702.55 1999 56031.37 2000 110318.38 2001 125473.88 2002 141886.41 2003 177624.56 2004 243430.37 2005 255064.49 2006 254239.7 2007 248731.15 2008 223949.51 2009 232031.72 2010 228049.95 2011 201747.33 2012 260646.93 2013 245317.58 2014 260957.58 2015 238693.97 2016 325985.47 2017 331294.56999999995 2018 336045.92 2019 289580.58 2020 220130.47 2021 191017.47 2022 240192.06