Year Number 1996 54.2553176879883 1998 45.2127647399902 2000 56.6137580871582 2002 52.9100532531738 2003 56.7839202880859 2004 57.7669906616211 2005 58.737865447998 2006 60.386474609375 2007 60.8695640563965 2008 62.980770111084 2009 56.3981056213379 2010 56.8720397949219 2011 55.4502372741699 2012 57.3459701538086 2013 60.1895751953125 2014 63.3333320617676 2015 65.7142868041992 2016 69.0476226806641 2017 68.0952377319336 2018 66.0377349853516 2019 66.9811325073242 2020 65.5660400390625 2021 58.4905662536621 2022 61.3207550048828