Year metric tons 1960 651576 1961 674920 1962 654311 1963 689299 1964 709330 1965 745249 1966 799698 1967 810052 1968 829986 1969 750969 1970 752458 1971 761294 1972 725937 1973 764694 1974 747194 1975 714393 1976 713101 1977 656550 1978 696895.3 1979 649366.3 1980 652110.9 1981 673271.88 1982 668074.64 1983 687885.47 1984 677794.54 1985 695266.4 1986 716684.58 1987 694891.48 1988 741153.08 1989 719597.4 1990 699221.8 1991 657306.5 1992 668299.5 1993 680185.5 1994 703920.6 1995 688459.3 1996 643217.9 1997 642478.5 1998 610416.5 1999 657039.8 2000 694452.6 2001 671905.7 2002 701925 2003 709038.7 2004 664898.2 2005 598482.8 2006 595153.9 2007 553685.7 2008 500162.8 2009 440199.3 2010 452243.5 2011 502006.02 2012 473308.8 2013 540519.91 2014 548074.9 2015 541788.04 2016 558484.89 2017 554362.3 2018 578656.4 2019 524109.56 2020 478461.6 2021 510779.44 2022 534875.51