Year Number 1996 77.8894500732422 1998 73.5 2000 56.2189064025879 2002 64.1791076660156 2003 63.1840782165527 2004 64.4230804443359 2005 66.0287094116211 2006 64.1148300170898 2007 49.2822952270508 2008 50.480770111084 2009 41.2322273254395 2010 44.0758285522461 2011 46.0093879699707 2012 46.948356628418 2013 45.0704231262207 2014 54.3269233703613 2015 58.5714302062988 2016 70.9523773193359 2017 70.476188659668 2018 77.1428604125977 2019 83.8095245361328 2020 75.2380981445313 2021 78.5714263916016 2022 78.7735824584961