Year	metric tons
1960	3400
1961	4200
1962	6000
1963	9000
1964	6300
1965	5000
1966	5000
1967	3700
1968	4300
1969	3000
1970	2400
1971	5400
1972	16400
1973	16200
1974	15050
1975	9142
1976	4715
1977	7372
1978	8783
1979	8934
1980	8892
1981	8208
1982	6840
1983	3251
1984	2991
1985	1993
1986	2337
1987	2269
1988	2479
1989	4722
1990	3318
1991	3124
1992	2456
1993	2162
1994	2516
1995	3616
1996	4156
1997	6328
1998	7013
1999	11000
2000	16250
2001	20800
2002	23560
2003	55860
2004	51466
2005	50018
2006	29835
2007	29728
2008	29960
2009	29884
2010	40000
2011	53173
2012	46500
2013	45000
2014	47000
2015	27000
2016	34592
2017	25195
2018	31042
2019	40058
2020	46000
2021	47200
2022	47670