Year	metric tons
1960	5000
1961	5000
1962	6000
1963	6000
1964	6000
1965	6000
1966	7500
1967	7500
1968	7500
1969	7500
1970	8800
1971	8900
1972	9100
1973	9200
1974	9475
1975	9650
1976	9824
1977	10053
1978	10606
1979	10838
1980	12929
1981	13502
1982	13009
1983	22485
1984	19380
1985	22844
1986	29271
1987	37877
1988	25002
1989	30983
1990	26852
1991	29170
1992	30023
1993	28884
1994	29569
1995	32121
1996	33687
1997	32139
1998	37284
1999	56641
2000	35446
2001	33280
2002	36694
2003	33712
2004	31061
2005	30562
2006	25661
2007	34170
2008	27299
2009	39426
2010	43116
2011	62907.02
2012	77531.66
2013	81409.01
2014	116963
2015	145976
2016	174273
2017	162549
2018	197900.53
2019	238698.32
2020	212750.3
2021	191128.54
2022	203294.05