Year Number 1996 34.1708526611328 1998 33.5 2000 84.5771179199219 2002 42.7860679626465 2003 54.7263679504395 2004 49.519229888916 2005 50.2392349243164 2006 27.2727279663086 2007 22.9665069580078 2008 25.480770111084 2009 17.5355453491211 2010 19.9052124023438 2011 18.3098583221436 2012 20.6572761535645 2013 17.3708915710449 2014 20.6730766296387 2015 21.4285717010498 2016 19.5238094329834 2017 20.4761905670166 2018 20 2019 21.9047622680664 2020 18.5714282989502 2021 23.8095245361328 2022 30.1886787414551