Year	metric tons
1960	400
1961	400
1962	800
1963	1200
1964	1000
1965	1000
1966	900
1967	500
1968	500
1969	500
1970	500
1971	500
1972	500
1973	800
1974	868
1975	973
1976	883
1977	3042
1978	2963
1979	2629
1980	3349
1981	2448
1982	3384
1983	2974
1984	3721
1985	3445
1986	4518
1987	5331
1988	4180
1989	3619
1990	5558
1991	5063
1992	4284
1993	3621
1994	4239
1995	3833
1996	4256.4
1997	3714.7
1998	4852.3
1999	5100.1
2000	5247.4
2001	5392
2002	5375.9
2003	5336.5
2004	6143
2005	6000
2006	5698
2007	5627.7
2008	6025
2009	5785
2010	5250
2011	5557.48
2012	5548.55
2013	5503
2014	5904
2015	5910
2016	5473.25
2017	5152.5
2018	4746.07
2019	5229.11
2020	4804.48
2021	4741.469999999999
2022	5663.91