Year Number 2004 0.7369264960289 2005 0.746284067630768 2006 0.703987658023834 2007 0.967931151390076 2008 0.984463036060333 2009 0.945724666118622 2010 0.919146716594696 2011 0.933990180492401 2012 0.952990829944611 2013 0.928985774517059 2014 1.08068346977234 2015 1.15167808532715 2016 1.15855598449707 2017 1.18432199954987 2018 1.16608023643494 2019 1.14571797847748 2020 1.09160161018372 2021 1.06857633590698 2022 1.12885904312134