Year	kg per hectare
1961	4000
1962	4000
1963	4000
1964	4000
1965	4000
1966	3500
1967	3360
1968	3440
1969	3185.2
1970	3185.2
1971	3259.3
1972	3169
1973	3142.9
1974	3142.9
1975	3214.3
1976	3214.3
1977	3214.3
1978	3357.1
1979	3333.3
1980	3312.5
1981	3235.3
1982	3333.3
1983	3351.4
1984	3315.8
1985	3300
1986	3000
1987	3333.3
1988	2998
1989	3325.6
1990	3566.8
1991	3333.3
1992	3374.3
1993	3465.7
1994	3580.8
1995	3758.1
1996	3333.3
1997	4292.2
1998	3333.3
1999	3000
2000	15000
2001	14285.7
2002	14857.1
2003	14825
2004	14444.4
2005	14418.6
2006	13571.4
2007	12181.8
2008	12727.3
2009	16750
2010	18774.2
2011	27640
2012	25878.8
2013	23958.3
2014	24485.7
2015	24218.8
2016	24742.9
2017	28225
2018	27837.8
2019	28125
2020	29241.4
2021	30400.2
2022	31620.7