Year	kg per hectare
1961	2275.9
1962	2689.7
1963	2769.4
1964	2823.4
1965	3106.5
1966	2908.1
1967	3476.7
1968	3570.9
1969	3532.1
1970	3374.4
1971	3875.5
1972	4168.7
1973	4407.5
1974	4179.3
1975	3696.6
1976	3440.8
1977	4051.4
1978	4630.5
1979	4516
1980	4854.2
1981	4729.1
1982	5007.5
1983	4949.9
1984	5976.8
1985	5742.8
1986	5301.6
1987	5706.2
1988	6080.8
1989	6099.1
1990	6082.6
1991	6536.2
1992	6485.4
1993	6512.6
1994	6542.6
1995	6456.5
1996	7082.4
1997	6890.3
1998	7415.4
1999	7260.4
2000	7231.5
2001	6729.2
2002	7453
2003	6125.3
2004	7518.7
2005	6965.4
2006	6800.5
2007	6520.6
2008	7252.8
2009	7412.4
2010	7068.6
2011	6919.3
2012	7254.5
2013	7084.8
2014	7579.1
2015	7590.5
2016	5690.9
2017	7306.7
2018	6829.1
2019	7491.9
2020	6394.9
2021	7171.3
2022	6654.9