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	2565
1993	2250
1994	1570
1995	1120
1996	650
1997	670
1998	437
1999	889
2000	893
2001	1331
2002	1020
2003	1064
2004	813
2005	739
2006	1056
2007	3650
2008	5100
2009	5190
2010	5050
2011	6300
2012	8850
2013	11700
2014	13925
2015	15130
2016	16381
2017	16690
2018	17000
2019	17560
2020	18350
2021	18930
2022	24000