Year	metric tons
1960	0
1961	0
1962	0
1963	0
1964	0
1965	0
1966	0
1967	0
1968	0
1969	0
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	0
1992	1507
1993	2993
1994	787
1995	715
1996	821
1997	499
1998	457
1999	980
2000	553
2001	944
2002	1020
2003	803
2004	583
2005	594
2006	645
2007	689
2008	809
2009	826
2010	897
2011	1122
2012	965
2013	697
2014	766
2015	869
2016	688.3
2017	773.3
2018	800.4
2019	662
2020	939.05
2021	611.23
2022	356