Year Number 1996 51.3661193847656 1998 56.8306007385254 2000 57.3770484924316 2002 49.1891899108887 2003 52.972972869873 2004 51.7412948608398 2005 51.9607849121094 2006 50.7317085266113 2007 49.5145645141602 2008 44.6601943969727 2009 43.0622024536133 2010 49.7607650756836 2011 49.7630348205566 2012 45.497631072998 2013 44.5497627258301 2014 44.711540222168 2015 37.1428565979004 2016 34.761905670166 2017 34.2857131958008 2018 25.238094329834 2019 20.4761905670166 2020 10.9523811340332 2021 10 2022 7.54716968536377