Year % 1997 7.07070707070707 1998 7.07070707070707 1999 12.1212121212121 2000 12.1212121212121 2001 12.1212121212121 2002 12.1212121212121 2003 12.1212121212121 2004 12.1212121212121 2005 11.1111111111111 2006 11.1111111111111 2007 12.1212121212121 2008 12.1212121212121 2009 14.1414141414141 2010 15.1515151515152 2011 12.1212121212121 2012 12.1212121212121 2013 12.1212121212121 2014 13.1313131313131 2015 16.1616161616162 2016 16.1616161616162 2017 20.2020202020202 2018 20.2020202020202 2019 19.1919191919192 2020 21.2121212121212 2021 24.2424242424242 2022 25.2525252525253 2023 26.2626262626263