Year % 2000 25.37631078717366 2001 25.261208845517448 2002 25.105037784662713 2003 24.708765782614755 2004 23.91331489498534 2005 23.925721757996648 2006 24.083766565670178 2007 24.14420871220118 2008 24.147166646438624 2009 23.987692509228456 2010 24.13567034552168 2011 24.062273476591365 2012 23.904633368026207 2013 23.252106992229308 2014 22.78352090862645 2015 23.055012920523527 2016 22.934315603188303 2017 22.595912074578365 2018 22.43149185802328 2019 22.284401311293138