Year	kilograms per hectare of arable land
1966	11.030685188741652
1967	11.53742232402282
1968	13.65490412822584
1969	14.51773514668246
1970	16.047018252165866
1972	20.579906590555268
1973	20.514345739531628
1974	21.023636363636363
1975	22.808801028214702
1976	24.74864175172868
1977	24.06386894529275
1978	25.839928347154014
1979	29.354406632642768
1980	32.81972149800926
1981	33.56886389401024
1982	35.89135376586971
1983	39.648359824498954
1984	44.209525868956696
1985	49.92427565006776
1986	53.762986171641266
1987	54.261820514814524
1988	54.554984384396036
1989	51.22200550311727
1990	53.10479194338012
1991	50.30006114279342
1992	50.63802915677434
1993	53.637466189655164
1994	48.66139989233331
1995	49.19168257479795
1996	50.25633935276003
1997	51.176419895917796
1998	52.694028303617564
1999	55.221377680586905
2000	57.13846343445253
2001	62.643087310249264
2002	65.15187215736124
2003	54.026874086353295
2004	60.35309316082585
2005	59.641125778652864
2006	59.974912258783164
2007	56.62443229825132
2008	55.31516494964626
2009	53.31347509970797
2010	52.37359557031747
2011	55.62901591459013
2012	52.23000945685721
2013	53.71427252260751
2014	51.19807486939491
2015	53.69344946171986
2016	51.94954940334657
2017	56.761925080586124
2018	55.99424599278724
2019	55.593584569491675
2020	54.609768443517936
2021	55.09259811769912