Year	metric tons
1961	7501313
1962	9274378
1963	9418967
1964	8306768
1965	8872202
1966	9233004
1967	10671297
1968	11583861
1969	11452764
1970	10258842
1971	13686715
1972	12076709
1973	11641386
1974	13275231
1975	14206900
1976	12771144
1977	13949322
1978	16339367
1979	13884855
1980	18665639
1981	11576278
1982	13147918
1983	13758534
1984	21032473
1985	20972014
1986	16519723
1987	20697404
1988	23833792
1989	19697663
1990	18775895.8
1991	19472661.44
1992	14495661.07
1993	17495716.71
1994	15249059.34
1995	11593292.98
1996	22385972.61
1997	19344464.25
1998	22579121.88
1999	18010899.04
2000	24581638.63
2001	18078871.22
2002	21742197.89
2003	21445314.48
2004	24842578
2005	14241390
2006	19088631
2007	24538959
2008	23995338
2009	17894933
2010	19880012.93
2011	22097143
2012	17547278
2013	25366791
2014	20581146.05
2015	20149310.35
2016	24056790
2017	16653669
2018	25348920
2019	20589030
2020	27320900
2021	25510560
2022	19292230