Year	kg per hectare
1961	984.5
1962	1027
1963	876.7
1964	1076.8
1965	856.5
1966	905.2
1967	1381.3
1968	995.3
1969	967.3
1970	888.4
1971	1133.4
1972	1149.8
1973	1104
1974	1133.1
1975	1014.9
1976	1110.2
1977	1298.8
1978	1246.8
1979	1175
1980	1187.4
1981	1121.9
1982	1169.1
1983	1146.2
1984	1180.6
1985	1169
1986	1076.1
1987	1001.8
1988	1156.4
1989	1179.4
1990	991.5
1991	1141
1992	481.6
1993	1488.8
1994	896.4
1995	1309.2
1996	1390.6
1997	1054.4
1998	1322.1
1999	1745.4
2000	1675.5
2001	1175.5
2002	1045.7
2003	1209
2004	1020.6
2005	777.8
2006	1444.7
2007	2467
2008	1598.7
2009	2124.3
2010	1906.9
2011	2094.3
2012	2087.1
2013	2068.8
2014	2218.1
2015	1590.6
2016	1347.4
2017	1903.1
2018	1531.2
2019	1874
2020	2004.4
2021	2319.1
2022	2008.9