Year kilograms per hectare of arable land 1961 1.378646173969915 1962 1.3479960899315737 1963 2.2209567198177678 1964 2.73 1965 2.1972256857855363 1966 3.4666460012399254 1967 5.893840916125039 1968 7.64289284598563 1969 10.075671250818598 1970 9.224951140065146 1971 12.597229551451187 1972 14.38233355306526 1973 12.902274911887215 1974 13.93711103832296 1975 17.982175324675325 1976 20.72554169402495 1977 23.407310704960835 1978 28.24398073836276 1979 31.77159420289855 1980 33.625163500467146 1981 34.65487804878049 1982 37.54725407362704 1983 38.79826030927835 1984 39.02223606353161 1985 47.65433617155472 1986 59.230258792302585 1987 55.0464 1988 58.13475935828877 1989 62.15471884248603 1990 63.62685714285714 1991 63.20472995639047 1992 71.78860294117646 1993 71.01488587495865 1994 72.18419834710744 1995 82.57137229152987 1996 78.98458265139116 1997 85.67442010309279 1998 82.84228791773779 1999 91.06396657023465 2000 95.44136597938144 2001 94.07188498402556 2002 97.7847533632287 2003 100.97018275088169 2004 110.7789508413065 2005 123.483460391117 2006 125.73024406332453 2007 118.42349237905898 2008 119.15465037338764 2009 144.32743031951054 2010 138.30472949982988 2011 128.52269102990033 2012 117.36236772486772 2013 135.70259271414506 2014 134.85413929040735 2015 137.4715789473684 2016 144.56295579219102 2017 152.47894905479012 2018 152.72362002567394 2019 152.38529315427448 2020 155.15088910442935 2021 157.28669288757786