Year	% of total secondary
1997	9.25030994415283
1998	9.25372982025146
1999	9.3606595993042
2000	9.25625038146973
2001	9.14459991455078
2002	9.0322904586792
2003	8.92177963256836
2004	8.80951976776123
2005	8.69678974151611
2006	8.58316040039062
2007	8.5161304473877
2008	8.44966983795166
2009	8.40167999267578
2010	8.31383037567139
2011	8.22793006896973
2012	8.08432960510254
2013	8.00514030456543
2014	7.88032007217407
2015	8.12436962127686
2016	8.75866985321045
2017	8.87133979797363
2018	8.89743041992188
2019	8.87467002868652
2020	8.51229000091553
2021	9.17940044403076
2022	9.18080997467041