Year	kg per hectare
1961	1181.8
1962	1181.8
1963	1217.4
1964	1217.4
1965	1250
1966	1250
1967	1280
1968	1280
1969	1230.8
1970	1230.8
1971	1259.3
1972	1259.3
1973	1285.7
1974	1285.7
1975	1266.7
1976	1333.3
1977	1333.3
1978	1333.3
1979	1419.4
1980	1437.5
1981	1424.2
1982	1411.8
1983	1388.9
1984	1352.9
1985	1333.3
1986	1200
1987	1384.6
1988	1333.3
1989	1333.3
1990	1363.6
1991	1340.2
1992	1339.9
1993	1333.3
1994	1341.3
1995	1344.2
1996	1347.3
1997	1350.4
1998	1353.8
1999	1357.2
2000	1357.3
2001	1359.2
2002	1364.1
2003	1333.3
2004	1377.5
2005	1357.1
2006	1404.7
2007	1448.3
2008	1437.7
2009	1436.8
2010	1416.7
2011	1400
2012	1666.7
2013	1666.7
2014	1623.5
2015	1604
2016	1597.7
2017	1601.7
2018	1609
2019	1630
2020	1644.5
2021	1655.5
2022	1666.5