Year	metric tons
1960	1300
1961	1300
1962	1300
1963	1300
1964	1900
1965	2000
1966	2000
1967	2000
1968	2000
1969	2000
1970	2000
1971	2500
1972	3000
1973	3000
1974	3087
1975	3654
1976	4510
1977	4731
1978	7732
1979	9799
1980	13213
1981	16356
1982	17441
1983	13482
1984	16277
1985	17260
1986	18802
1987	19028
1988	22057
1989	23895
1990	25607
1991	22025
1992	21601
1993	21230
1994	20219
1995	16463
1996	16387
1997	18156
1998	16371
1999	12410
2000	13114
2001	12300
2002	11500
2003	10600
2004	10500
2005	10420
2006	10500
2007	10500
2008	11400
2009	12800
2010	14550
2011	17200
2012	19900
2013	22500
2014	28353.13
2015	24833.54
2016	29356.54
2017	31258.35
2018	29306.96
2019	26569.26
2020	26671.55
2021	22734
2022	26161