Year	% of total teachers
2006	75.6755294799805
2007	81.8632431030273
2008	78.9038619995117
2009	79.3529891967773
2010	78.9725112915039
2011	79.239372253418
2012	79.060188293457
2013	79.1387329101562
2018	80.6610412597656
2019	80.5093994140625
2020	81.0842208862305
2021	82.6601333618164
2022	81.8085479736328