Year metric tons 1960 33800 1961 36500 1962 45700 1963 59800 1964 76600 1965 76500 1966 85696 1967 98990 1968 74080 1969 130954 1970 171517 1971 232662 1972 281189 1973 221664 1974 219146 1975 261391 1976 246601 1977 271933 1978 274631 1979 236979 1980 231566 1981 240510 1982 244163 1983 251503 1984 269563 1985 276216 1986 319818 1987 381814 1988 362050 1989 361675 1990 395872 1991 362538 1992 423425 1993 372619 1994 335437 1995 352844 1996 476744 1997 447127 1998 445541 1999 496770 2000 454346 2001 450353 2002 375182 2003 393547 2004 420443.4 2005 381637.89 2006 378642.99 2007 331175.01 2008 342518.14 2009 304584 2010 351458.65 2011 349760.3 2012 356346.57 2013 289884.74 2014 323425.15 2015 344060.91 2016 323916.57 2017 367767.76 2018 358743.37 2019 317305.72 2020 370686.15 2021 392761.55 2022 519627.27