Year	metric tons
1960	8446066
1961	10790271
1962	12834096
1963	13009640
1964	15554692
1965	14298623
1966	15976859
1967	18040192
1968	19293050
1969	17894122
1970	20927202
1971	19374263
1972	14132464
1973	12391419
1974	14434305
1975	13818249
1976	15019635
1977	14022421
1978	15569557
1979	15631076
1980	14852966
1981	15397908
1982	16734806
1983	14870795.8
1984	17194978.47
1985	18978710.540000003
1986	21598677.409999996
1987	22002145.15
1988	24379404.900000002
1989	24383339.99
1990	24432794.380000003
1991	25433488.66
1992	33646353.51
1993	35717867.16
1994	39913116.16
1995	39912302.97
1996	42757524.41
1997	41604380.66
1998	38099393.44
1999	42009028.03
2000	44062608
2001	40849524.7
2002	41380212.68
2003	39073754.45
2004	42556293.589999996
2005	42422503.41
2006	40616056.4
2007	41033021.71
2008	40866429.86
2009	40527893.730000004
2010	38337813.129999995
2011	43000583.239999995
2012	39912419.029999994
2013	41266848.06
2014	40010435.13
2015	41734297.45
2016	40395583.58
2017	40932260.49
2018	43959694.46999999
2019	40740656.04
2020	40448783.21000001
2021	41511290.70999999
2022	40119542.519999996