Year kg per hectare 1961 2203.3029548754016 1962 2430.221366014941 1963 2580.2211379968057 1964 2378.6691922017326 1965 2731.875818755094 1966 2763.27392738539 1967 2781.5133828587213 1968 2858.920497838886 1969 3108.653907735493 1970 2960.731187165245 1971 3376.0369615977756 1972 3458.5666926812564 1973 3293.162356397431 1974 2733.7913050669567 1975 3178.522000349537 1976 3266.6396618448102 1977 3392.4351975638106 1978 3712.9383427875164 1979 3934.251216259715 1980 3425.2117898375054 1981 3840.1486848299965 1982 3955.5218146586444 1983 3178.8690714560903 1984 3842.10773654317 1985 4180.0323680384845 1986 4170.4845518866705 1987 4111.606533873253 1988 3186.7628773853294 1989 3888.920792449385 1990 4231.813490678294 1991 4023.066780168508 1992 4678.5111013958185 1993 3895.8180880004365 1994 4910.069813378108 1995 4189.30664855705 1996 4614.236287889396 1997 4653.065518670102 1998 5012.691412548312 1999 5125.631321676128 2000 5130.861611478292 2001 5053.2434310952285 2002 4846.748952005617 2003 5254.024261827035 2004 6029.282187728719 2005 5745.134413751884 2006 5623.094402575097 2007 5932.766051111402 2008 5914.836141568026 2009 6416.074094561494 2010 6329.8276820796755 2011 6174.018740034213 2012 5422.422577601863 2013 6635.49691413728 2014 6854.176946758975 2015 6676.542140193245 2016 7773.803115628059 2017 7419.097434678282 2018 7260.43869080045 2019 7103.774839141771 2020 7209.163333873061 2021 7134.4068736824065 2022 7119.331391817804