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	124
1993	90
1994	118
1995	128
1996	26
1997	26
1998	19
1999	9
2000	25
2001	28
2002	38
2003	58
2004	85
2005	56
2006	51
2007	26
2008	36
2009	26
2010	44
2011	50
2012	50
2013	50
2014	50
2015	50
2016	50
2017	50
2018	50
2019	50
2020	50
2021	0