Year % of total secondary 1999 25.1046009063721 2000 25.0213508605957 2001 25.5883598327637 2002 25.2883396148682 2004 28.0636806488037 2005 25 2006 29.6309108734131 2007 28.8704299926758 2008 28.8617897033691 2011 27.7264308929443 2012 29.4972705841064 2013 28.7570095062256 2018 34.3786010742188 2019 37.0726203918457 2021 37.6780395507812 2022 38.8546485900879