Year Number 1996 53.0054626464844 1998 53.0054626464844 2000 52.4590148925781 2002 57.2972984313965 2003 57.8378372192383 2004 38.8059692382813 2005 49.5098037719727 2006 36.0975608825684 2007 39.3203887939453 2008 39.3203887939453 2009 42.5837326049805 2010 40.6698570251465 2011 42.6540298461914 2012 41.2322273254395 2013 37.9146919250488 2014 27.884614944458 2015 22.8571434020996 2016 19.5238094329834 2017 18.5714282989502 2018 17.1428565979004 2019 15.7142858505249 2020 16.1904754638672 2021 15.2380952835083 2022 17.4528293609619