Year Number 1996 8.60215091705322 1998 0 2000 8.51063823699951 2002 1.58730161190033 2003 5.8201060295105 2004 9.85221672058105 2005 13.1707315444946 2006 14.1463413238525 2007 19.4174766540527 2008 19.4174766540527 2009 11.9617223739624 2010 16.1904754638672 2011 17.5355453491211 2012 18.9573459625244 2013 21.3270149230957 2014 23.5576915740967 2015 25.7142848968506 2016 28.0952377319336 2017 38.5714302062988 2018 35.7142868041992 2019 26.6666660308838 2020 27.1428565979004 2021 27.619047164917 2022 26.4150943756104