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	6
1993	3
1994	3
1995	4
1996	4
1997	5
1998	5
1999	5
2000	7
2001	12
2002	13
2003	13
2004	18
2005	19
2006	24
2007	24
2008	24
2009	24
2010	11
2011	6
2012	6
2013	6
2014	6
2015	6
2016	6
2017	0
2018	0
2019	0
2020	0.1
2021	1.5
2022	2.5