Year	metric tons
1960	34786
1961	41895
1962	43308
1963	33317
1964	38248
1965	40643
1966	44529
1967	44916
1968	34265
1969	39245
1970	39461
1971	38354
1972	41792
1973	44297
1974	51260
1975	47593
1976	44644
1977	59865
1978	68233
1979	83135
1980	103738
1981	107487
1982	106206
1983	99311
1984	86274
1985	94949
1986	102906
1987	100413
1988	120337
1989	168786
1990	143331
1991	114164
1992	113267
1993	116775
1994	117417
1995	128890
1996	116018
1997	113851
1998	123291
1999	160253
2000	159711
2001	158485
2002	195624
2003	175321
2004	212988
2005	234864
2006	252959
2007	233754
2008	241899
2009	214667
2010	209446
2011	214493
2012	222894
2013	275432
2014	292441
2015	268371
2016	273175
2017	310741
2018	301052
2019	265179
2020	259209
2021	271027
2022	307055