Year	kg per hectare
1961	2417.4
1962	2962.2
1963	2925.2
1964	3120.8
1965	2852.2
1966	2878
1967	3483.3
1968	3619.6
1969	3447.5
1970	3179.6
1971	3788.6
1972	3770.2
1973	3873.4
1974	4178.8
1975	3864.4
1976	3495.7
1977	3885.2
1978	4285.2
1979	4108.3
1980	4227.6
1981	4161.6
1982	4568.3
1983	4362.6
1984	5036.6
1985	5072.7
1986	5084.8
1987	4898.4
1988	5173.7
1989	5203.6
1990	5411.1
1991	5986.1
1992	5335.6
1993	5711.7
1994	5826.2
1995	6107.8
1996	6282
1997	6484.9
1998	6330.2
1999	6699.9
2000	6452.9
2001	7055.2
2002	6251.5
2003	5764.5
2004	7355.3
2005	6723.2
2006	6486.6
2007	6182.9
2008	7118.8
2009	7201.4
2010	6685.2
2011	6458.3
2012	6964.9
2013	7318
2014	8050.3
2015	7497.8
2016	7182.1
2017	7269.9
2018	6178.9
2019	6952
2020	7133.3
2021	6998.1
2022	7126.1