Year	% of total teachers
2005	76.4884567260742
2006	74.9374084472656
2007	73.4315414428711
2008	71.3354568481445
2009	69.6039428710938
2010	67.3105087280273
2011	63.1684799194336
2012	66.3487701416016
2013	64.5034790039062
2014	66.3935470581055
2015	67.5852203369141
2016	70.0466079711914
2017	71.0534133911133
2018	71.6129684448242
2019	69.6949768066406