Year Number 1996 62.5 1998 52.1739120483398 2000 40.7608680725098 2002 40.5405387878418 2003 43.2432441711426 2004 29.8507461547852 2005 29.4117641448975 2006 26.470588684082 2007 23.7864074707031 2008 24.2718448638916 2009 29.6650714874268 2010 27.2727279663086 2011 24.1706161499023 2012 30.8056869506836 2013 28.9099521636963 2014 31.730770111084 2015 30 2016 30.4761905670166 2017 30.4761905670166 2018 35.7142868041992 2019 33.8095245361328 2020 38.5714302062988 2021 39.0476188659668 2022 41.5094337463379