Year	metric tons
1960	2500
1961	2500
1962	2800
1963	2800
1964	2800
1965	3000
1966	3000
1967	3000
1968	3300
1969	4000
1970	5400
1971	5200
1972	6600
1973	6400
1974	7679
1975	7038
1976	6660
1977	7668
1978	7113
1979	6540
1980	6364
1981	7157
1982	9810
1983	9458
1984	10388
1985	12229
1986	12899
1987	17351
1988	17190
1989	16980
1990	14176
1991	18662
1992	18961
1993	20689
1994	18287
1995	16571
1996	12034
1997	14143
1998	12176
1999	12290
2000	9702
2001	11045
2002	10762
2003	11001
2004	10321
2005	10255
2006	9124
2007	8500
2008	7116
2009	8293.4
2010	7933.5
2011	7843.3
2012	6864
2013	8313.21
2014	15435.52
2015	16575.190000000002
2016	19236.69
2017	26240.36
2018	31411.079999999998
2019	37327.49
2020	29287.69
2021	32344.82
2022	34829.490000000005