Year Number 1996 0.7869011759758 1998 0.773185670375824 2000 0.75122994184494 2002 0.698325157165527 2003 0.682984054088593 2004 0.582346558570862 2005 0.58463853597641 2006 0.547179877758026 2007 0.530372381210327 2008 0.642759263515472 2009 0.653302133083344 2010 0.642825543880463 2011 0.631379723548889 2012 0.59927225112915 2013 0.601454555988312 2014 0.529373943805695 2015 0.355818599462509 2016 0.328430950641632 2017 0.237134978175163 2018 0.401309967041016 2019 0.470356702804565 2020 0.497693717479706 2021 0.374506026506424 2022 0.28908696770668