Year	metric tons
1960	300
1961	500
1962	900
1963	700
1964	1100
1965	1300
1966	1200
1967	1300
1968	1300
1969	1400
1970	1300
1971	1500
1972	1700
1973	1700
1974	1634
1975	1700
1976	1700
1977	2958
1978	2238
1979	1491
1980	1419
1981	788
1982	982
1983	1479
1984	1555
1985	1727
1986	2296
1987	2214
1988	2092
1989	1782
1990	1911
1991	2071
1992	2115
1993	2212
1994	1599
1995	1499
1996	1577
1997	1530
1998	1837
1999	1828
2000	1701
2001	2250
2002	2171
2003	2544
2004	2039
2005	2048
2006	2163
2007	2207
2008	2386
2009	2648
2010	2182
2011	2411.47
2012	2379.63
2013	2856.67
2014	2665
2015	2472.5
2016	2740.27
2017	2444.15
2018	2540.42
2019	2048.89
2020	1893.89
2021	1211.58
2022	1855.61