Year Number 1996 36.4130439758301 1998 35.8695640563965 2000 41.3043479919434 2002 45.4054069519043 2003 49.1891899108887 2004 48.756217956543 2005 51.470588684082 2006 50 2007 50 2008 46.6019401550293 2009 28.2296657562256 2010 23.4449768066406 2011 21.8009471893311 2012 19.4312801361084 2013 24.1706161499023 2014 17.3076915740967 2015 19.5238094329834 2016 20 2017 16.1904754638672 2018 13.8095235824585 2019 11.9047622680664 2020 14.7619047164917 2021 21.9047622680664 2022 25.943395614624