Year metric tons 1961 1847205 1962 2332325 1963 1432038 1964 1629550 1965 2006634 1966 1858708 1967 2051724 1968 2899566 1969 2473690 1970 2112408 1971 1588491 1972 3901326 1973 1603339 1974 1960870 1975 1372508 1976 2109366 1977 1444700 1978 1780469 1979 1480600 1980 1891900 1981 2035800 1982 2065900 1983 1821700 1984 1100160 1985 2932251 1986 2280630 1987 1728000 1988 2590600 1989 1496700 1990 3454800 1991 2672653 1992 2959211 1993 3239908 1994 2830150 1995 2540110 1996 3004520 1997 2215530 1998 2431550 1999 1604520 2000 904480 2001 1818903.07 2002 4124870 2003 3521487.33 2004 3316916.71 2005 3708150 2006 3785500 2007 3752471 2008 2225411 2009 2650113 2010 4362383 2011 4270151 2012 4790950 2013 6498524 2014 7048606 2015 3471115.91 2016 4007685 2017 3735255 2018 2615277 2019 6913550 2020 8885242 2021 5302192 2022 3421743