Year	metric tons
1960	4000
1961	4000
1962	4000
1963	5000
1964	5000
1965	5600
1966	7000
1967	8000
1968	8700
1969	9500
1970	9800
1971	9400
1972	11200
1973	13900
1974	8689
1975	10778
1976	10513
1977	13914
1978	15900
1979	9121
1980	6996
1981	5944
1982	5000
1983	4548
1984	4339
1985	4164
1986	2465
1987	4983
1988	4654
1989	4582
1990	3088
1991	5709
1992	6683
1993	7886
1994	10653
1995	9679
1996	13720
1997	13937
1998	15184
1999	19837
2000	22519
2001	20033
2002	19558
2003	15654
2004	19668
2005	28239
2006	32198
2007	27316
2008	31312
2009	37853
2010	40978
2011	33527
2012	33783.99
2013	40979.01
2014	54364
2015	41534
2016	45022.99
2017	50982
2018	54553.99
2019	51309.99
2020	43466.54
2021	55274.54
2022	53732.32