Year	metric tons
1960	16825893
1961	17918933
1962	18226492
1963	18260862.1
1964	18404859.1
1965	20087084.4
1966	20863615.8
1967	22309449
1968	23502134
1969	22778881
1970	24261268
1971	25160695
1972	25551699
1973	26174985
1974	26420099
1975	25812066
1976	27438753
1977	27160189
1978	26901339.1
1979	26524821.700000003
1980	27115158.9
1981	27834850.16
1982	28251420.259999998
1983	29100622.020000003
1984	30167723.89
1985	29333686.980000004
1986	30381647.380000003
1987	30839766.58
1988	31063198.540000003
1989	30121258.3
1990	28530634.3
1991	27119540.07
1992	27837852.76
1993	26903248.72
1994	26418894.44
1995	25761425.17
1996	25233984.76
1997	25726100.5
1998	24517456.01
1999	23843992.03
2000	23124247.439999998
2001	23172369.72
2002	22190977.28
2003	21841150.32
2004	21395141.09
2005	21112593.080000002
2006	20895128.31
2007	20517705.759999998
2008	20032604.84
2009	19593398.16
2010	19852623.28
2011	19659743.880000003
2012	18628582.55
2013	18941419.21
2014	19487522.560000002
2015	19149141.499999996
2016	18015496.23
2017	18887072.46
2018	18650677.470000003
2019	17874602.399999995
2020	17119603.950000003
2021	16709785.619999997
2022	14312739.570000002