Year	kg per hectare
1961	3691.4
1962	4277.4
1963	3986.9
1964	4395.8
1965	3673.4
1966	3513.6
1967	4206.5
1968	3939
1969	3981.2
1970	3768.4
1971	4320.5
1972	3982.5
1973	4640.1
1974	5042.4
1975	4472.6
1976	4779.9
1977	4768.5
1978	5797.9
1979	5402.7
1980	5689.2
1981	5975.9
1982	6740.9
1983	6351.6
1984	7188.9
1985	6174.1
1986	7419.9
1987	6268
1988	6194
1989	6750.6
1990	6990.1
1991	7063.4
1992	7459.2
1993	7998.4
1994	7164.5
1995	7769.2
1996	8292.9
1997	7176.1
1998	7307
1999	7469.8
2000	7905.5
2001	7280.5
2002	7313.9
2003	7956.8
2004	8066.3
2005	7879.7
2006	7854.2
2007	7289.7
2008	8332.3
2009	9032.9
2010	8569.3
2011	7800.8
2012	8545
2013	8630.1
2014	9073.7
2015	8752.8
2016	7776.9
2017	8794.5
2018	7905.1
2019	8654.2
2020	7919.9
2021	7872.3
2022	8942.6