Year % of total teachers 2006 87.1123733520508 2007 86.5411911010742 2008 83.0658187866211 2009 83.1448287963867 2010 82.0913009643555 2011 80.7713317871094 2012 82.1446075439453 2013 79.7851409912109 2014 79.935417175293 2015 81.2399978637695 2016 82.2160873413086 2017 83.5612411499023 2018 83.3662719726562 2019 78.5086975097656 2020 78.6946716308594 2021 79.8777770996094 2022 78.8469009399414