Year	metric tons
1960	2500
1961	2800
1962	2800
1963	3300
1964	2800
1965	2700
1966	3000
1967	3000
1968	3500
1969	3500
1970	2400
1971	2800
1972	3600
1973	3600
1974	3800
1975	3900
1976	3915
1977	3982
1978	3820
1979	3890
1980	3500
1981	3676
1982	3369
1983	3540
1984	4113
1985	4564
1986	4657
1987	4523
1988	4227
1989	4483
1990	4228
1991	4829
1992	3945
1993	2957
1994	2716
1995	2749
1996	3002
1997	3009
1998	2959
1999	2975
2000	2759
2001	2850
2002	2679
2003	2915
2004	2807
2005	2952
2006	2904
2007	2869
2008	3300
2009	3433
2010	3362
2011	3564
2012	3474
2013	3600
2014	3576
2015	3616
2016	3584
2017	3665
2018	3396
2019	3740.4399999999996
2020	3844.0299999999997
2021	3849.9300000000003
2022	3985.9300000000003