Year % of total teachers 1999 68.7580795288086 2000 69.7072296142578 2001 69.5402221679688 2002 70.7838973999023 2003 72.5560607910156 2004 71.7230911254883 2005 71.3164672851562 2006 71.38037109375 2007 71.7964477539062 2008 72.2615203857422 2009 73.1872711181641 2010 76.0028381347656 2011 75.1020278930664 2012 71.9083404541016 2014 71.549919128418 2015 65.2906188964844 2016 66.2763824462891 2017 62.8701210021973 2018 63.8255615234375 2019 81.0389404296875 2020 72.9985580444336 2021 80.118049621582 2022 66.8114166259766