Year	kilograms per hectare of arable land
1961	2.2929930394431555
1962	1.6903908045977012
1963	2.2646924829157173
1964	2.1347543352601157
1965	2.14249910490512
1966	2.6308784383318544
1967	3.500439753737907
1968	3.6888462544693468
1969	3.4241376329212416
1970	2.829575653664809
1971	3.2477259202584374
1972	4.482168451226709
1973	4.585883927078107
1974	5.020058260507699
1975	7.849773008666942
1976	6.552006552006552
1977	2.6080597985050376
1978	0.941924509962741
1979	2.747185095180235
1980	6.529126213592233
1981	6.075060532687651
1982	6.385140562248996
1983	3.416
1984	7.039840637450199
1985	7.523809523809524
1986	4.758893280632411
1987	3.047244094488189
1988	6.279434850863423
1989	3.868235294117647
1990	6.3984375
1991	4.334630350194552
1992	4.612403100775194
1993	3.6188261048022987
1994	3.8933333333333335
1995	3.199851457572569
1996	5.722168905950096
1997	4.662650602409639
1998	2.2848484848484847
1999	2.3687423687423688
2000	2.507238341649726
2001	5.141670737664875
2002	3.472486227979902
2003	3.495457567028584
2004	4.608968311227038
2005	2.6752
2006	2.5509333333333335
2007	3.588611212136956
2008	3.840898504218208
2009	7.963796811868052
2010	10.238106018301917
2011	8.071859420355473
2012	3.327887329050661
2013	2.61245839205321
2014	4.200625934512964
2015	4.474324803486839
2016	9.382396369879816
2017	8.338665398416234
2018	7.103071992927786
2019	7.103071992927786
2020	7.103071992927786
2021	7.103071992927786