Year	% of total teachers
2004	82.9352722167969
2005	82.902458190918
2006	82.0473709106445
2007	80.7090835571289
2008	78.4198608398438
2011	76.8407592773438
2012	77.5455703735352
2013	78.7753601074219
2014	78.8686065673828
2015	79.05029296875
2016	77.5850982666016
2017	77.5240631103516
2018	81.0307083129883
2019	79.9611434936523
2020	78.5587692260742
2021	77.9907302856445