Year	metric tons
1960	3643190
1961	3886384
1962	4018650
1963	3865394
1964	3730487
1965	3889901
1966	3798181
1967	3605306
1968	3903989
1969	3841139
1970	4187696
1971	4201366
1972	3945509
1973	3975344
1974	3930839
1975	3879625
1976	4225967
1977	4313222
1978	4890523
1979	5036716
1980	5080765
1981	5147488.08
1982	5382052.04
1983	5524940.109999999
1984	6026842.24
1985	6194523.52
1986	6413489
1987	7310146
1988	7375848.96
1989	7142061.33
1990	7306400.44
1991	6745395.16
1992	6605856.38
1993	6770820.74
1994	6710035.56
1995	6089994
1996	5995766
1997	6157572
1998	5877718
1999	6010503
2000	5821508
2001	6083789
2002	6104728
2003	6141077
2004	6206410
2005	6108117
2006	6010755
2007	5845779
2008	5342329
2009	5223060
2010	5373083
2011	6075257.33
2012	5910691.23
2013	5944858.03
2014	5820478.5
2015	5861171.2
2016	5731908.97
2017	5880384.16
2018	5651152.6899999995
2019	5678245.66
2020	5034641.45
2021	5062442.17
2022	4967404.83