Year	kilograms per hectare of arable land
1972	0.235
1973	0.1
1974	0.13636363636363635
1975	1.7241379310344827
1976	3.3449612403100777
1977	2.1904761904761907
1978	1.0452961672473868
1979	0.42214532871972316
1980	0.3436426116838488
1981	5.215017064846417
1982	1.3559322033898304
1983	7.070707070707071
1984	9.03010033444816
1985	9.30232558139535
1986	7.128712871287129
1987	7.1245901639344265
1988	3.0879478827361564
1989	3.883495145631068
1990	3.604501607717042
1991	1.9169329073482428
1992	1.5873015873015872
1993	1.2618296529968454
1994	1.2539184952978057
1995	1.2307692307692308
1996	0.6153846153846154
1997	0.6153846153846154
1998	1.3323076923076924
1999	0.9230769230769231
2000	0.9230769230769231
2001	0.9230769230769231
2002	5.578461538461538
2003	3.6123076923076924
2004	5.107692307692307
2005	8.344615384615384
2006	8.458461538461538
2007	9.058461538461538
2008	10.516923076923076
2009	12.021538461538462
2010	3.16
2011	5.649230769230769
2012	10.088184615384616
2013	10.14123076923077
2014	13.078953846153846
2015	27.34163076923077
2016	31.82861538461539
2017	60.62107692307692
2018	44.15
2019	39.86233846153846
2020	21.272707692307694
2021	28.250307692307693