Year Number 1996 0.650729417800903 1998 0.832761347293854 2000 0.796799182891846 2002 0.900155961513519 2003 0.844509065151215 2004 0.763184726238251 2005 0.720574915409088 2006 0.610028147697449 2007 0.633248209953308 2008 0.644565641880035 2009 0.607087075710297 2010 0.578393816947937 2011 0.576675236225128 2012 0.692556440830231 2013 0.635518550872803 2014 0.764807999134064 2015 0.552077174186707 2016 0.727797985076904 2017 0.594937205314636 2018 0.623929619789124 2019 0.498032212257385 2020 0.527586281299591 2021 0.600826501846313 2022 0.621043562889099