Year	kg per hectare
1961	1481.5
1962	1481.5
1963	1481.5
1964	1481.5
1965	1481.5
1966	1448.3
1967	1433.3
1968	1466.7
1969	1508.2
1970	1516.1
1971	1548.4
1972	1538.5
1973	1529.4
1974	1514.3
1975	1527.8
1976	1515.2
1977	1515.2
1978	1515.2
1979	1500
1980	1500
1981	1515.2
1982	1515.2
1983	1500
1984	1555.6
1985	1516.7
1986	1500
1987	1600
1988	1764.7
1989	2000
1990	1928.6
1991	2117.6
1992	2222.2
1993	2193.5
1994	2263.2
1995	2222.2
1996	2250
1997	2222.2
1998	1931.4
1999	2100
2000	2230
2001	2173.9
2002	2107.4
2003	2131.1
2004	2145.7
2005	2223.9
2006	2454.5
2007	2307.7
2008	2153.8
2009	1538.5
2010	1615.2
2011	2099.5
2012	2099
2013	2096
2014	2065
2015	2033.2
2016	2012.5
2017	2002.3
2018	2002.4
2019	2024.4
2020	2040.2
2021	2042.7
2022	2045.2