Year metric tons 1961 2274011 1962 2305937 1963 2229471 1964 2349312 1965 2019628 1966 2648957 1967 2934871 1968 3046205 1969 3406075 1970 3070552 1971 3545643 1972 3318492 1973 3787094 1974 4014005 1975 3704116 1976 4277716 1977 4203640 1978 4628713 1979 3982485 1980 4826198 1981 4356211 1982 5026041 1983 5075517 1984 5353319 1985 5551181 1986 5108350 1987 4964599 1988 5359343 1989 5009116 1990 5289752 1991 5044859 1992 4322590 1993 4206456 1994 4435935 1995 4451882 1996 4494851.92 1997 5010607.17 1998 4772664.73 1999 4809095.2 2000 4494383.16 2001 4837093.57 2002 4762611.9 2003 4269509.66 2004 5323713.99 2005 4907056.68 2006 4467510.5 2007 4766039.24 2008 5756463.63 2009 5164152.4 2010 4866648.45 2011 5712206.55 2012 4883379.22 2013 4599433.26 2014 5720308.58 2015 4853895.01 2016 5701697.09 2017 4874849.22 2018 4787200 2019 5399310 2020 5649770 2021 5316150 2022 5205750