Year	kg per hectare
1961	1300.7036510959244
1962	1405.3666883404821
1963	1519.6410458895932
1964	1589.9964835403455
1965	1700.298738934102
1966	1771.0429564060462
1967	1824.3924311855385
1968	1839.6407174615915
1969	1813.0363827462954
1970	1967.9236326893283
1971	2036.4509659860362
1972	2000.9641258301392
1973	2116.580900433389
1974	2206.664432464317
1975	2227.7770501614086
1976	2292.9565947171463
1977	2215.366051818323
1978	2418.082196868815
1979	2545.380009501054
1980	2541.515801162742
1981	2624.610860031655
1982	2877.514058347544
1983	3054.277786281828
1984	3230.5518286747197
1985	3150.0921567177284
1986	3186.900132424534
1987	3215.021078095925
1988	3240.6662444563617
1989	3324.694072727871
1990	3496.860284786015
1991	3503.765845388786
1992	2860.945147733054
1993	2905.4860824877896
1994	2884.7697372786583
1995	2998.572617369054
1996	3164.521078769362
1997	3258.729116007558
1998	3343.741964020727
1999	3414.581480727543
2000	3179.574051801422
2001	3391.434785398362
2002	3400.2867068892556
2003	3407.010370879851
2004	3581.72190157543
2005	3551.7349941169164
2006	3659.339305427427
2007	3688.91746392059
2008	3901.823634588403
2009	3858.4038778979893
2010	3970.366271733411
2011	4131.146140659346
2012	4104.0727450316
2013	4287.866083526673
2014	4361.622402442902
2015	4439.347351219545
2016	4438.244388619595
2017	4634.423804604621
2018	4575.719373072607
2019	4682.184151937196
2020	4666.996207665951
2021	4638.346009982522
2022	4780.109873589757