Year	kg per hectare
1961	408.5
1962	477.9
1963	473.1
1964	522.5
1965	485.7
1966	495.4
1967	452.3
1968	625.8
1969	484.5
1970	516.6
1971	444.5
1972	461.2
1973	436.6
1974	488.2
1975	558.1
1976	499.4
1977	528.8
1978	576.4
1979	580.1
1980	569.8
1981	576.6
1982	568.3
1983	514.9
1984	589.9
1985	708.8
1986	699.5
1987	641.7
1988	726.9
1989	672.9
1990	600.2
1991	876.6
1992	871.5
1993	936.2
1994	787.9
1995	851.1
1996	916.5
1997	704.5
1998	889
1999	912.9
2000	856.4
2001	967.8
2002	942.7
2003	996.3
2004	940.7
2005	1127.2
2006	1203.9
2007	936.1
2008	1039.9
2009	1002
2010	1062.7
2011	995.1
2012	1203
2013	1156.5
2014	1225.8
2015	1168.9
2016	1136.8
2017	1009
2018	1152.3
2019	1156.1
2020	1261.7
2021	1095.7
2022	1204.1