Year	% of total teachers
2009	63.7704887390137
2010	61.9030914306641
2011	60.5199813842773
2012	60.2363891601562
2013	61.7368698120117
2014	62.6076393127441
2015	64.4178924560547
2016	64.9177780151367
2017	66.2558517456055
2018	67.6698608398438
2019	65.4612808227539
2020	64.5706024169922
2021	63.5827598571777