Year	kilograms per hectare of arable land
1961	1.1538461538461537
1962	1.7307692307692308
1963	2.5
1964	2.8957528957528957
1965	3.281853281853282
1966	3.9285714285714284
1967	4.222007722007722
1968	7.722007722007722
1969	12.184971098265896
1970	13.732692307692307
1971	14.615384615384615
1972	13.846153846153847
1973	10.889312977099237
1974	8.17490494296578
1975	4.364326375711575
1976	4.943502824858757
1977	0.00946969696969697
1979	0.18556701030927836
1980	1.0491803278688525
1981	1.054989816700611
1982	3.368217054263566
1983	3.076923076923077
1984	5.555555555555555
1985	8.901515151515152
1986	4.761904761904762
1987	3.4136546184738954
1988	1.4
1989	1.0737051792828685
1990	3.288100208768267
1991	2.9106029106029108
1992	4.166666666666667
1993	4.123711340206185
1994	4.016913319238901
1995	4.2105263157894735
1996	8.385744234800839
1997	8.16326530612245
1998	10.183299389002036
1999	10.1010101010101
2000	10.204081632653061
2001	9.438775510204081
2004	2.6510204081632653
2005	0.0653061224489796
2006	0.053061224489795916
2007	0.35918367346938773
2008	0.746938775510204
2009	4.578
2010	0.5411764705882353
2011	1.3150943396226416
2012	2.2479811320754717
2013	2.927490909090909
2014	1.8858363636363635
2015	4.131963636363636
2016	2.167981818181818
2017	2.3090545454545452
2018	4.214654545454546
2019	4.2566
2020	9.957709090909091
2021	9.746709090909093
