Year	kg per hectare
1961	549.4
1962	544.3
1963	573.3
1964	588.3
1965	588.7
1966	530.8
1967	636.3
1968	461.2
1969	699
1970	475.6
1971	655.7
1972	370.9
1973	508
1974	740.5
1975	708.2
1976	706.8
1977	508.1
1978	833.2
1979	616.8
1980	547.4
1981	904.7
1982	684.3
1983	573.3
1984	612.1
1985	819.9
1986	761.7
1987	841.4
1988	712.1
1989	847.3
1990	795
1991	822.6
1992	798.6
1993	836.5
1994	757.7
1995	872
1996	758.5
1997	716.7
1998	667.8
1999	870.4
2000	879.4
2001	887.1
2002	651.6
2003	1090.7
2004	974.5
2005	1201.1
2006	879
2007	722.5
2008	1174.2
2009	1134.6
2010	1196.5
2011	966.9
2012	1221.3
2013	1124.1
2014	1111.5
2015	1376.1
2016	1350.6
2017	1476.2
2018	1644.3
2019	1601.3
2020	1821.6
2021	1854.7
2022	1931.9