Year Number 1996 30.8510646820068 1998 21.2765960693359 2000 11.640212059021 2002 10.582010269165 2003 18.5929641723633 2004 13.5922327041626 2005 12.1359224319458 2006 18.3574886322021 2007 14.9758453369141 2008 12.9807691574097 2009 14.2180099487305 2010 13.7440757751465 2011 19.4312801361084 2012 21.8009471893311 2013 24.1706161499023 2014 22.380952835083 2015 24.761905670166 2016 24.761905670166 2017 20.9523811340332 2018 20.2830181121826 2019 15.0943393707275 2020 13.2075471878052 2021 16.9811325073242 2022 16.5094337463379