Year	kg per hectare
1961	1509.8
1962	1452.3
1963	1555.6
1964	1659.5
1965	1862.3
1966	2037.9
1967	2046
1968	1918.3
1969	1953.8
1970	1801.7
1971	2355.9
1972	2711
1973	2384.2
1974	2295.4
1975	2446.5
1976	3116.4
1977	2950.8
1978	2898.8
1979	2941
1980	2993.9
1981	2627.2
1982	3313.1
1983	2918.5
1984	3195.4
1985	3102.6
1986	3181.1
1987	2821
1988	3265.9
1989	3049.3
1990	3010.8
1991	3191.7
1992	2128.3
1993	2422.7
1994	2772.9
1995	3085.1
1996	2430.3
1997	3541.4
1998	2642.7
1999	3188.1
2000	1927.8
2001	3029.4
2002	2512.5
2003	2534.9
2004	3997.4
2005	3334.2
2006	3102.3
2007	1645.2
2008	3247.3
2009	2824.8
2010	3329.7
2011	3993
2012	2364.1
2013	3863.2
2014	4069.2
2015	3543.9
2016	3971.3
2017	5227.7
2018	5997.2
2019	5457.5
2020	3398.6
2021	5187.8
2022	3634.1