Year	kilograms per hectare of arable land
1961	2.642528973180929
1962	2.937823427944174
1963	3.402852437622347
1964	2.9999219146527154
1965	3.1605515246972553
1966	3.3005420721941605
1967	3.889743026575884
1968	4.60230825878575
1969	4.6997359712316165
1970	5.672955216683744
1971	6.3089234449760765
1972	6.914283001400527
1973	6.993522104191092
1974	7.782452295304571
1975	8.822696302649133
1976	10.570836171560368
1977	10.890487902939716
1978	12.782414132421161
1979	14.199175142249773
1980	13.454159592529711
1981	14.461406618007135
1982	14.75471675072354
1983	15.071908626831688
1984	15.669649298364012
1985	16.171971932433376
1986	15.218334183318651
1987	15.548651817116061
1988	16.598840237508245
1989	16.387605685932062
1990	16.990585085868553
1991	16.43002920421359
1992	16.52002160240327
1993	15.849054956567288
1994	11.909155276074356
1995	9.474097933648848
1996	9.550719868366928
1997	10.67610169677186
1998	9.486517253646388
1999	10.891268115205593
2000	10.697642121482442
2001	10.06219920197856
2002	10.313535361740167
2003	8.559938497253919
2004	10.120646547237127
2005	10.036454646987696
2006	10.445386489619453
2007	10.43898775663294
2008	11.427609153523345
2009	10.61260120351531
2010	11.25060034051447
2011	10.993273223179239
2012	9.884355903698392
2013	8.622347074823885
2014	10.072762742598641
2015	10.29203631671955
2016	12.427803696159424
2017	12.506919968465976
2018	11.937605636599303
2019	11.786117067017736
2020	14.306790002627743
2021	13.605306533865967