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	5
1978	11
1979	22
1980	40
1981	57
1982	89
1983	120
1984	282
1985	130
1986	124
1987	137
1988	167
1989	138
1990	106
1991	74
1992	57
1993	50
1994	50
1995	57
1996	58
1997	67
1998	67
1999	67
2000	50
2001	150
2002	330
2003	385
2004	395
2005	402
2006	435
2007	546
2008	546
2009	546
2010	570
2011	571
2012	840
2013	1195
2014	1575
2015	1955
2016	2315
2017	3855
2018	5508
2019	6908
2020	8508
2021	9808
2022	10118