Year % 2000 22.579 2001 22.5 2002 25.565 2003 27.654 2004 26.831 2005 30.478 2006 31.403 2007 31.998 2008 31.465 2009 33.227 2010 32.047 2011 33.655 2012 34.773 2013 33.119 2014 34.288 2015 33.886 2016 35.734 2017 35.226 2018 33.935 2019 33.261 2020 35.072 2021 35.186 2022 36.527 2023 36.026