Year	kg per hectare
1961	1067.5
1962	1163.1
1963	1161.9
1964	956
1965	829.8
1966	1067.2
1967	1072.4
1968	746.6
1969	801
1970	932.8
1971	871.5
1972	1222.1
1973	1073.6
1974	1416.5
1975	1253
1976	967
1977	1123.1
1978	1023.5
1979	913.5
1980	1168.9
1981	1261.5
1982	1252.9
1983	1128.4
1984	1192.5
1985	1338.9
1986	1501.5
1987	1824.6
1988	1838.9
1989	1960.8
1990	1878.3
1991	2024.9
1992	2099.9
1993	2154.6
1994	2067.9
1995	2568.9
1996	2449.7
1997	1639.1
1998	1943.3
1999	1738.3
2000	2414.9
2001	2911.7
2002	2467.5
2003	2372
2004	2727.6
2005	2703.1
2006	2684.8
2007	2189.7
2008	2687.7
2009	2618.9
2010	2624.9
2011	2763.2
2012	2889.3
2013	2981.4
2014	3386
2015	3268.6
2016	3155.5
2017	2898.5
2018	2970.1
2019	2940.6
2020	3100
2021	2178.2
2022	2415.3