Year	metric tons
1960	20000
1961	22000
1962	23000
1963	23000
1964	23000
1965	25000
1966	27000
1967	30700
1968	37000
1969	43000
1970	49570
1971	58925
1972	36291
1973	33190
1974	43697
1975	33921
1976	33834
1977	37897
1978	41467
1979	24541
1980	21598
1981	58779
1982	56288
1983	81600
1984	57676
1985	66277
1986	76614
1987	88397
1988	77666
1989	76000
1990	66000
1991	67637
1992	66054
1993	59452
1994	53746
1995	56147
1996	63324
1997	74127
1998	98043
1999	104527
2000	114456
2001	140142
2002	156131
2003	199650
2004	270733
2005	304877
2006	165312
2007	223207
2008	195328
2009	216900
2010	276238
2011	372011
2012	437709
2013	387833
2014	378339
2015	403776
2016	609754
2017	794580
2018	967706.75
2019	720849.51
2020	678425
2021	762868.24
2022	780382.8