Year	% of total teachers
2005	78.953742980957
2008	56.4137115478516
2009	54.6672897338867
2011	37.8987884521484
2012	46.5521392822266
2013	40.683650970459
2014	46.4948883056641
2015	49.8874206542969
2016	57.8000907897949
2017	60.8404312133789
2018	64.9422073364258
2019	59.6080093383789