Year % of tax revenue 1985 47.942609637249596 1986 50.06093102607848 1987 61.981093300452116 1988 74.34545454545454 1989 69.00963512873165 1993 74.2254980997351 1994 72.85677944543373 1995 72.92165071770334 1996 68.68596881959911 1997 68.92529488859765 1998 67.94280987829376 1999 63.72668064907826 2000 63.07977736549165 2005 20.318139995378477 2006 16.277686504029358 2007 16.467280347601402 2008 19.207566725588727 2009 15.014717667278326 2010 21.33558694754645 2011 27.69828538505692 2012 25.66144581191054 2013 9.5863920600818 2014 7.399840017391036 2015 6.094068958178791 2016 6.061057087016908 2017 4.335748999525329 2018 4.442559847870376 2019 4.27099584771337 2020 4.093152513408823