Year	metric tons
1961	115000
1962	120000
1963	125000
1964	130000
1965	135000
1966	141000
1967	142000
1968	152000
1969	163000
1970	190000
1971	200000
1972	210000
1973	225000
1974	248000
1975	229000
1976	245000
1977	256000
1978	244000
1979	249000
1980	243000
1981	269000
1982	284000
1983	290000
1984	298000
1985	289000
1986	288000
1987	297700
1988	297700
1989	294090
1990	180000
1991	100000
1992	110000
1993	65000
1994	50000
1995	56200
1996	94450
1997	168400
1998	209400
1999	196300
2000	183400
2001	145000
2002	110000
2003	100000
2004	110000
2005	154800
2006	164000
2007	231800
2008	295150
2009	293000
2010	296090
2011	291000
2012	297000
2013	270000
2014	266000
2015	296000
2016	335180
2017	247495
2018	257995
2019	276400
2020	279000
2021	255600
2022	288000