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	30
1988	30
1989	50
1990	70
1991	70
1992	80
1993	10
1994	10
1995	40
1996	40
1997	40
1998	40
1999	40
2000	40
2001	40
2002	40
2003	160
2004	288
2005	388
2006	388
2007	240
2008	110
2009	110
2010	110
2011	10
2012	10
2013	10
2014	10
2015	10
2016	10
2017	10
2018	10
2019	10
2020	10
2021	10
2022	10