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	500
1980	1391
1981	3992
1982	933
1983	655
1984	423
1985	396
1986	478
1987	1097
1988	386
1989	615
1990	837
1991	586
1992	825
1993	445
1994	125
1995	125
1996	110
1997	125
1998	125
1999	125
2000	125
2001	125
2002	125
2003	125
2004	125
2005	125
2006	125
2007	125
2008	125
2009	125
2010	125
2011	125
2012	125
2013	125
2014	125
2015	125
2016	125
2017	125
2018	125
2019	125
2020	125
2021	125
2022	125