Year	% of total teachers
2012	83.2607574462891
2013	74.3593826293945
2014	71.9927062988281
2015	71.8479309082031
2016	72.9695587158203
2017	70.5352020263672
2018	70.7474594116211
2019	69.9588088989258
2020	67.500862121582