Year % of total teachers 2003 71.8070526123047 2004 73.2645416259766 2005 75.9329528808594 2006 77.8613662719727 2007 79.0949172973633 2008 80.4789810180664 2009 87.7007369995117 2010 76.2556991577148 2011 76.9879989624023 2012 77.6330032348633 2013 84.2735214233398 2015 81.5039978027344 2016 75.4019012451172 2017 74.7675476074219