Year	metric tons
1966	30
1967	18
1968	30
1969	45
1970	60
1971	80
1972	92
1973	28
1974	37
1975	60
1976	51
1977	30
1978	35
1979	96
1980	29
1981	45
1982	59
1983	68
1984	29
1985	38
1986	40
1987	48
1988	57
1989	60
1990	50
1991	55
1992	50.95
1993	50.22
1994	49.43
1995	45
1996	48.63
1997	48.94
1998	49.35
1999	49.73
2000	48
2001	50.77
2002	50
2003	55
2004	60
2005	61.12
2006	65
2007	64.85
2008	68
2009	66.32
2010	63.44
2011	71.88
2012	70.12
2013	71.77
2014	72.08
2015	74.57
2016	64.71
2017	51.47
2018	36.94
2019	22.98
2020	11.4
2021	10.68
2022	15.74