Year Number 1996 57.5268821716309 1998 54.5454559326172 2000 52.6595726013184 2002 51.3227500915527 2003 44.9735450744629 2004 42.8571434020996 2005 48.2926826477051 2006 40.9756088256836 2007 49.5145645141602 2008 50 2009 52.6315803527832 2010 52.8571434020996 2011 50.7108993530273 2012 46.445499420166 2013 44.5497627258301 2014 41.8269233703613 2015 36.1904754638672 2016 30.9523811340332 2017 29.5238094329834 2018 31.9047622680664 2019 30.4761905670166 2020 32.8571434020996 2021 31.9047622680664 2022 30.6603775024414