Year	% of total secondary
1999	17.5006904602051
2000	17.8779201507568
2001	17.7884902954102
2002	17.9211502075195
2003	18.2567100524902
2004	18.0385093688965
2005	18.4359893798828
2006	18.6333103179932
2007	18.1109199523926
2008	18.1580200195312
2010	17.716760635376
2011	17.9285297393799
2012	18.1273593902588
2013	17.8376903533936
2014	18.0342197418213
2015	18.3532905578613
2016	18.4491291046143
2017	18.4999294281006
2018	18.8044891357422
2019	19.4021606445312
2020	19.6702003479004
2021	19.7741298675537