Year	metric tons
1960	6234918
1961	6634258
1962	7309113
1963	7683484
1964	8708464
1965	8888441
1966	10069284
1967	9717701
1968	10256590
1969	10410264
1970	10638335
1971	11775683
1972	12083871
1973	12551163
1974	13269843
1975	13559986
1976	14343542
1977	15996108.5
1978	17181596.900000002
1979	17472623.8
1980	17822340.1
1981	18968777.29
1982	19473528.04
1983	20782774.720000003
1984	23015853.73
1985	24689131.66
1986	27194786.610000003
1987	28494016.54
1988	30126177.04
1989	32344000.8
1990	31181759.57
1991	33772523.26
1992	44809971.78
1993	47782705.32
1994	53596055.65000001
1995	59090043.910000004
1996	62795572.45
1997	62639228.16000001
1998	62014833.66
1999	66182857.02
2000	67691063.01
2001	68397118.81
2002	71026303.60999998
2003	72505062.88
2004	76679822.34
2005	78302247.19
2006	80086630.61999997
2007	81892002.27
2008	83408038.02999999
2009	86299237.61000003
2010	87420935.08000001
2011	89822852.03999998
2012	93780264.32000001
2013	96201046.13000001
2014	99694379.93000002
2015	101830411.48
2016	104550249.09000003
2017	107532005.09999998
2018	109713499.02999999
2019	111768024.31000003
2020	113453968.37000002
2021	116055243.27000003
2022	118849458.65999995