Year	kilograms per hectare of arable land
1961	0.059026579219882636
1962	0.047980669658267174
1963	0.05591991715567829
1964	0.02657921988263721
1965	0.15982050396962375
1966	0.16568864342423195
1967	0.3872972040041422
1968	0.4832585433206766
1969	0.6089057645840524
1970	0.6586123576113221
1971	0.7704521919226787
1972	0.8508802209181913
1973	1.6415548675610596
1974	3.051079876585533
1975	1.9686353019686353
1976	2.617124394184168
1977	2.4426494345718903
1978	2.2271714922048997
1980	0.2868983104877271
1981	1.467304625199362
1982	1.7241379310344827
1983	1.8530351437699681
1984	2.238567316917173
1985	2.268370607028754
1986	1.320754716981132
1987	1.6981132075471699
1988	1.522635029659694
1989	1.5240459199503569
1990	1.7720745493431103
1991	2.588801926550271
1992	3.0149611011370436
1993	1.5584569732937685
1994	2.0648967551622417
1995	2.50233918128655
1996	3.5
1997	2.1805555555555554
1998	4.6722222222222225
1999	4.861111111111111
2000	4.861111111111111
2001	4.72972972972973
2002	3.1150540540540534
2003	2.7313947368421054
2004	2.3295263157894737
2005	3.5426923076923074
2006	3.416076923076923
2007	3.326230769230769
2008	3.6487743589743595
2009	3.2784375
2010	4.033333333333333
2011	2.758348837209302
2012	2.4241612903225804
2013	2.470136
2014	2.4832846153846155
2015	2.444782692307692
2016	2.4092981132075466
2017	3.061577358490566
2018	3.0081396226415094
2019	2.354316981132076
2020	2.244792452830189
2021	2.244792452830189