Year kilograms per hectare of arable land 1966 0.011450381679389313 1967 0.015186028853454821 1968 0.0264750378214826 1969 0.40617935192162774 1970 0.07507507507507508 1971 0.29850746268656714 1972 0.5278810408921933 1973 0.9 1974 1.062730627306273 1975 4.4475421863536315 1976 2.239178283198826 1977 2.1562729273661043 1978 8.131868131868131 1979 10.717423133235725 1980 8.28623718887262 1981 8.760233918128655 1982 9.046783625730994 1983 11.407894736842104 1984 14.239766081871345 1985 13.629737609329446 1986 11.793002915451895 1987 6.773255813953488 1988 12.936046511627907 1989 12.617561683599419 1990 14.74655285620486 1991 12.827225130890053 1992 10.595065312046444 1993 6.781750924784217 1994 7.191149354640443 1995 8.022045315370484 1996 4.918032786885246 1997 12.009956440572495 1998 11.255115089514067 1999 9.75048480930834 2000 9.836893203883495 2001 11.118690313778991 2002 8.197879858657243 2003 4.496805111821086 2004 13.664150943396226 2005 3.808080808080808 2006 8.423580786026202 2007 21.406593406593405 2008 14.634538152610443 2009 12.040990606319385 2010 19.457784663051896 2011 12.4031007751938 2012 16.022574750830564 2013 30.376353039134056 2014 22.431848127600556 2015 1.7949630801687764 2016 18.9824237999635 2017 12.732158211521925 2018 1.6485946872322192 2019 10.572918825561311 2020 10.628963730569948 2021 10.628963730569948