Year % 2000 35.633006759881056 2001 35.21167137119354 2002 34.93999764149061 2003 34.70533102894616 2004 34.38805145117346 2005 34.051559627913576 2006 33.68580347334361 2007 33.361047778248846 2008 32.97358672408364 2009 32.537227524117064 2010 32.19455828844348 2011 31.851453142723688 2012 31.649472486199127 2013 31.52853106112829 2014 31.3657012884979 2015 31.090527643695154 2016 30.943504537325058 2017 30.84905806988461 2018 30.779804454538112 2019 30.75888651032516