Year	metric tons
1960	20015
1961	20015
1962	20015
1963	18015
1964	18013
1965	20014
1966	21114
1967	22515
1968	24019
1969	24016
1970	26066
1971	24369
1972	19643
1973	20260
1974	69949
1975	68317
1976	72713
1977	73545
1978	72105
1979	72453
1980	52922
1981	55805
1982	106174
1983	112033
1984	117923
1985	120626
1986	154311
1987	215620
1988	235192
1989	260383
1990	269076
1991	275730
1992	327513
1993	343887
1994	333999
1995	368297
1996	381702
1997	400267
1998	400534
1999	411997
2000	424541
2001	413692
2002	401655
2003	441837
2004	474320
2005	522328
2006	575347
2007	561316
2008	562568
2009	599924
2010	663684
2011	734895
2012	833785.01
2013	879101.02
2014	940600.99
2015	977240
2016	1087850.99
2017	1195366.99
2018	1268111.63
2019	1282681.01
2020	1271400.05
2021	1258202.73