Year % 1997 10.206896551724142 1998 10.919540229885062 2000 11.585365853658537 2001 12.282840597378847 2002 13.466711499663752 2003 13.708836239010582 2004 14.735467015022865 2005 16.237014236244715 2006 16.639209225700164 2007 17.306466011988274 2008 17.800845828527493 2009 18.464052287581698 2010 18.73716632443532 2011 20.535166318890393 2012 21.375802349521617 2013 22.45702005730659 2014 22.158043504977265 2015 23.636991028295377 2016 23.810068649885583 2017 24.016932159964362 2018 24.074279995552107 2019 24.078116025272834 2020 24.86859011797688 2021 25.925053028517564 2022 26.33820651548291 2023 27.03399765533412