Year	metric tons
1960	9000
1961	9000
1962	9000
1963	11300
1964	19200
1965	16800
1966	14100
1967	10200
1968	19100
1969	22000
1970	32090
1971	27100
1972	31500
1973	26700
1974	22446
1975	19532
1976	25537
1977	23101
1978	22862
1979	51785
1980	49623
1981	22445
1982	20101
1983	18503
1984	16524
1985	17000
1986	16000
1987	16000
1988	21461
1989	21555
1990	22629
1991	13485
1992	18073
1993	19941
1994	25147
1995	28208
1996	30737
1997	31302
1998	22574
1999	22423
2000	20767
2001	33300
2002	26000
2003	17200
2004	12936
2005	26008
2006	59075
2007	53032
2008	34580
2009	28245
2010	19348
2011	31541
2012	51077
2013	56853
2014	59000
2015	27296
2016	31300
2017	35220
2018	36936
2019	40069
2020	34770.17
2021	43679.69
2022	44550