Year Number 1996 40.7035179138184 1998 50.5 2000 54.2288551330566 2002 57.2139320373535 2003 49.7512435913086 2004 47.5961532592773 2005 50.2392349243164 2006 40.6698570251465 2007 41.6267929077148 2008 43.75 2009 47.3933639526367 2010 49.7630348205566 2011 51.1737098693848 2012 51.1737098693848 2013 46.478874206543 2014 49.038459777832 2015 45.238094329834 2016 43.8095245361328 2017 37.6190490722656 2018 35.7142868041992 2019 33.8095245361328 2020 37.6190490722656 2021 37.6190490722656 2022 30.1886787414551