Year	kg per hectare
1961	1031
1962	1043
1963	1055.2
1964	1056.6
1965	1071.7
1966	1075.8
1967	1091.9
1968	1049.7
1969	1112.5
1970	1097.3
1971	1117
1972	1148.7
1973	1066.4
1974	1175.4
1975	1117.7
1976	1238.9
1977	918.8
1978	803.9
1979	964.6
1980	1016.2
1981	1046.7
1982	1039.6
1983	1044.3
1984	1041.1
1985	1009.7
1986	991.2
1987	969.7
1988	957.7
1989	972.3
1990	1026.7
1991	987.7
1992	976.1
1993	949.2
1994	923.9
1995	925.8
1996	974
1997	1004.1
1998	913.6
1999	969.4
2000	931.8
2001	826.5
2002	920.4
2003	920.8
2004	933.8
2005	956.8
2006	962.9
2007	959.8
2008	961.1
2009	994.6
2010	977.4
2011	982.2
2012	1077
2013	1059.9
2014	895
2015	978.1
2016	1012.3
2017	894.6
2018	709.9
2019	1599.3
2020	927.7
2021	1054.8
2022	1055.4