Year	metric tons
1960	18517241
1961	19873368
1962	20549092
1963	20714500.1
1964	21527956.1
1965	23073107.4
1966	24702851.8
1967	25516371
1968	26824134
1969	25900221
1970	27719794
1971	28958962
1972	28790823
1973	29665339
1974	30469112
1975	29978924
1976	32117896
1977	32214328
1978	32624720.1
1979	33184491.7
1980	33934018.9
1981	35120810.949999996
1982	35197598.1
1983	36708371.74
1984	38992918.019999996
1985	38831980.22
1986	40403941.18
1987	40343596
1988	41153944.279999994
1989	41158209.730000004
1990	38092224.48
1991	36862250.41
1992	38579760.300000004
1993	37489906.36
1994	38574443.61000001
1995	37974537.449999996
1996	36793162.10999999
1997	36652317.67000001
1998	32368086.400000002
1999	33545670.430000003
2000	32570361.259999998
2001	32322618.319999997
2002	32102432.14
2003	31027419.95
2004	31711852.25
2005	30791078.330000006
2006	29918177.82
2007	29375304.58
2008	28285367.55
2009	27306409.79
2010	26815594.880000003
2011	27065111.49
2012	25950156.109999992
2013	25627710.69999999
2014	26494608.78
2015	25947642.930000003
2016	24135841.360000007
2017	25871573.220000003
2018	25891234.980000004
2019	24882028.999999993
2020	23922488.70000001
2021	24039810.050000016
2022	21979341.52999999