Year	metric tons
1960	3100
1961	3100
1962	3300
1963	3300
1964	2900
1965	2800
1966	2500
1967	2500
1968	2200
1969	2200
1970	2100
1971	2200
1972	2100
1973	2000
1974	2000
1975	2275
1976	2663
1977	2881
1978	3197
1979	3597
1980	2557
1981	1784
1982	2202
1983	2655
1984	2354
1985	1496
1986	1327
1987	1191
1988	1611
1989	1867
1990	1949
1991	2115
1992	2046
1993	2162
1994	2583
1995	3749
1996	3043
1997	3672
1998	3785
1999	3799
2000	5454
2001	5043
2002	3237
2003	3786
2004	3342
2005	3561
2006	2806
2007	2305
2008	2423
2009	2312
2010	1180.03
2011	1490.1
2012	1881.76
2013	1912.39
2014	1810.39
2015	1825.85
2016	1851.46
2017	1555.66
2018	1640.93
2019	1515.3
2020	1579.69
2021	1580
2022	1581.29