Year % 2000 24.235658879525424 2001 23.94704346907102 2002 23.833748738451817 2003 23.625826485003568 2004 23.187154400460038 2005 22.883530910753738 2006 22.50031540958012 2007 22.231070019275077 2008 22.070697266961858 2009 21.837648079458685 2010 21.733423871686668 2011 21.51806660269178 2012 21.252130553220965 2013 20.731249954525254 2014 20.36637733062669 2015 20.33795544105156 2016 20.21694665628107 2017 19.914170850677316 2018 19.718429296067587 2019 19.584589406552528