Year	kg per hectare
1961	805.7
1962	831.3
1963	958.6
1964	804.4
1965	801.4
1966	760.2
1967	702.5
1968	581.1
1969	638.5
1970	573.8
1971	708.1
1972	668
1973	903
1974	764.6
1975	1052.2
1976	1007.6
1977	1005.9
1978	999.6
1979	1166.3
1980	1020.2
1981	1003.1
1982	1429.5
1983	1300.9
1984	1270.7
1985	1366.8
1986	1126.6
1987	1274.3
1988	1220.1
1989	1489.2
1990	1506.5
1991	1234.1
1992	1087.6
1993	1227.4
1994	1151.7
1995	1702.8
1996	1588.1
1997	1101.2
1998	1198.8
1999	1766.4
2000	1440.7
2001	2043.5
2002	1899.5
2003	858.1
2004	1370.6
2005	1101.6
2006	1326.7
2007	1427.3
2008	1333.9
2009	1110.4
2010	1647.9
2011	1390.4
2012	1314.8
2013	1418
2014	1669.1
2015	1617.2
2016	1711.1
2017	1692
2018	1938.5
2019	1883.7
2020	1828.3
2021	1747.1
2022	1593.1