Year % of total secondary 1999 20.9602699279785 2000 20.7420806884766 2001 20.5534992218018 2002 20.1928997039795 2003 20.4224891662598 2004 20.6585502624512 2005 21.2514591217041 2006 21.7737197875977 2007 22.7194309234619 2008 23.1875305175781 2009 23.7887897491455 2010 24.5295295715332 2011 25.3628902435303 2012 26.0694103240967 2013 25.9443206787109 2014 27.6921691894531 2015 27.9816398620605 2016 28.5398902893066 2017 28.5051803588867 2018 29.0146198272705 2019 29.2581996917725 2020 29.3614196777344 2021 29.3882598876953 2022 29.29833984375