Year % of total secondary 1997 14.6332502365112 1998 14.5329999923706 1999 14.4653797149658 2000 14.3837099075317 2001 14.2584400177002 2002 14.2785301208496 2003 14.2214603424072 2004 14.4645299911499 2005 14.5808401107788 2006 14.2703399658203 2007 14.3837995529175 2008 14.5834999084473 2009 14.8835601806641 2010 15.140700340271 2011 15.113320350647 2012 15.5873203277588 2013 18.2115592956543 2014 18.5030994415283 2015 18.7039794921875 2016 19.0148506164551 2017 19.2575397491455 2018 19.4869995117188 2019 19.4270896911621 2020 19.2961597442627 2021 19.6719207763672 2022 19.6105003356934