Year % 2001 12.057501693037 2002 11.988329360447983 2003 11.880206873002962 2004 10.196916717984177 2005 8.67844746815396 2006 9.648153082233257 2007 11.597918292546458 2008 8.40787171717855 2009 10.46037818866809 2010 13.119357424188033 2011 12.492662622439763 2012 13.674154490819301 2013 12.860677807522118 2014 16.552091012361647 2015 17.71406848007745 2016 17.37476034321878 2017 17.734544158324603 2018 18.819126500984645 2019 19.8778887135407 2020 23.164421125226735 2021 27.064071243060102 2022 26.237892521425763 2023 20.778729409550017