Year	kg per hectare
1961	699.2
1962	700.8
1963	692
1964	692.1
1965	646
1966	695.1
1967	699.8
1968	710.5
1969	710.8
1970	727.1
1971	725.4
1972	746.5
1973	741.1
1974	744
1975	747.7
1976	745.8
1977	739.2
1978	728.9
1979	799
1980	798.7
1981	822.5
1982	833.9
1983	833.5
1984	850.2
1985	799.6
1986	789.9
1987	821.8
1988	797.9
1989	802
1990	799.8
1991	802.4
1992	782.2
1993	790.6
1994	793.4
1995	765.8
1996	780.9
1997	801.7
1998	811
1999	787.3
2000	786.6
2001	786.6
2002	772
2003	771.5
2004	771.7
2005	771.7
2006	771.6
2007	771.6
2008	771.6
2009	771.6
2010	784.9
2011	771.1
2012	771.6
2013	772.1
2014	769
2015	768.9
2016	785.5
2017	794.1
2018	812.4
2019	835.6
2020	877.8
2021	879
2022	816