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	1874
1993	2462
1994	980
1995	284
1996	93
1997	71
1998	81
1999	74
2000	86
2001	99
2002	143
2003	167
2004	26
2005	26
2006	26
2007	26
2008	26
2009	255.1
2010	517.2
2011	537
2012	274.8
2013	403.9
2014	443.6
2015	450
2016	439
2017	470
2018	512
2019	736
2020	775
2021	2039
2022	2248