Year Number 1996 62.5 1998 63.1840782165527 2000 65.6716384887695 2002 63.1840782165527 2003 57.2139320373535 2004 58.1730766296387 2005 56.25 2006 58.6538467407227 2007 58.1730766296387 2008 58.1730766296387 2009 56.8720397949219 2010 55.9241714477539 2011 56.3380279541016 2012 57.7464790344238 2013 57.2769966125488 2014 59.6059112548828 2015 58.6206893920898 2016 58.1280784606934 2017 57.6354675292969 2018 57.7669906616211 2019 59.9033813476563 2020 59.4202880859375 2021 61.835750579834 2022 61.3526573181152