Year	metric tons
1960	87800
1961	81200
1962	60100
1963	130300
1964	121000
1965	134400
1966	116836
1967	187913
1968	133268
1969	169230
1970	173841
1971	160410
1972	174957
1973	146374
1974	128738
1975	121724
1976	152660
1977	164465
1978	244131
1979	349682
1980	426855
1981	470180
1982	503466
1983	557297
1984	566942.09
1985	578082.12
1986	579855.93
1987	624698
1988	669904.5
1989	450487.3
1990	379204.1
1991	356949
1992	447374
1993	545535
1994	587576
1995	630978
1996	520429.5
1997	459155
1998	487201
1999	573827
2000	503352
2001	527736
2002	566682
2003	507772
2004	550482
2005	426496
2006	533048
2007	632450
2008	494118
2009	463917
2010	485925
2011	514790.15
2012	432452.64
2013	374141.36
2014	302228.97
2015	431918.78
2016	335345.27
2017	354470.5
2018	314242.51
2019	463194.96
2020	364404.88
2021	328158
2022	335002.9