Year % 2001 8.273714249691334 2002 9.867040287813966 2003 10.268157023169943 2004 12.659104518323257 2005 7.878761567027078 2006 7.741665539712672 2007 8.354020620623393 2008 7.960533908622283 2009 7.3964214118710165 2010 7.398048588862125 2011 8.43917051021436 2012 8.376072685814693 2013 11.427445700389308 2014 11.678804345967464 2015 12.080057708060789 2016 12.914749407451916 2017 11.363260939386057 2018 11.84465190462448 2019 11.767236652297518 2020 18.496603419535074 2021 14.63575393857585 2022 18.053392652416427 2023 18.92938476603815