Year Number 1996 0.668098986148834 1998 0.638672411441803 2000 0.637169182300568 2002 0.74562805891037 2003 0.723233759403229 2004 0.728531181812286 2005 0.745595574378967 2006 0.690555095672607 2007 0.699741125106812 2008 0.657143592834473 2009 0.707632899284363 2010 0.741072177886963 2011 0.726919293403625 2012 0.725595772266388 2013 0.705827534198761 2014 0.68024754524231 2015 0.631029963493347 2016 0.641597270965576 2017 0.758043825626373 2018 0.798121333122253 2019 0.751704931259155 2020 0.822011470794678 2021 0.93204939365387 2022 0.872202396392822