Year	kilograms per hectare of arable land
1961	1.7607470049330514
1962	0.34385964912280703
1963	0.47368421052631576
1964	0.5344827586206896
1965	0.5517241379310345
1966	0.5689655172413793
1967	1.516195727084769
1968	1.4035087719298245
1969	2.036363636363636
1970	1.2862978091347939
1971	1.7455555555555555
1972	1.2777777777777777
1973	1.1111111111111112
1974	0.7567567567567568
1975	0.05405405405405406
1976	0.05263157894736842
1980	4.05
1981	9.5
1982	5.369458128078818
1983	2.3529411764705883
1984	0.8333333333333334
1987	0.2
1988	0.028985507246376812
1989	0.0814111261872456
1990	1.1096075778078485
1991	1.5405405405405406
1992	2.972972972972973
1993	3.928955866523143
1994	2.864864864864865
1995	2.6486486486486487
1996	2.108108108108108
1997	5.918918918918919
1998	2.0594594594594593
2002	6.937275675675677
2003	5.483745945945946
2004	6.8122837837837835
2005	10.457659459459462
2006	10.319516216216217
2007	10.158405405405405
2008	9.869448648648646
2009	13.25330810810811
2010	15.627177161152613
2011	20.08756870746529
2012	26.884593342252852
2013	24.230450947447785
2014	26.936244223072404
2015	29.667337962892486
2016	21.294794252879353
2017	39.775701970734836
2018	42.19268737044714
2019	42.76319732983687
2020	44.241180365372216
2021	49.58371921223933