Year	% of total teachers
1998	75.9468536376953
1999	75.6449813842773
2000	75.557373046875
2001	73.6590118408203
2002	73.3634872436523
2003	72.4276809692383
2004	73.7448425292969
2005	71.0980072021484
2006	71.0768432617188
2007	70.5823287963867
2008	71.8109817504883
2009	68.1877517700195
2010	69.0892868041992
2011	69.6876220703125
2012	68.8364105224609
2013	67.7039794921875
2014	65.7039566040039
2015	65.7923431396484
2016	65.0028991699219
2017	64.4177932739258
2018	66.3263778686523
2019	65.9944915771484
2020	66.5083618164062
2021	66.0985565185547