Year % 2000 30.572109972828848 2001 30.406692199160517 2002 30.045535304186988 2003 29.790755820090066 2004 29.525456482120518 2005 28.98999476539143 2006 28.383935600972652 2007 28.081888546978384 2008 27.385366863956502 2009 26.815467947286123 2010 26.21841733186598 2011 25.797979648970063 2012 25.390049661052483 2013 24.924469314584975 2014 24.795213506479723 2015 24.473527131103676 2016 24.254142128713326 2017 24.06536772164188 2018 24.029165305917854 2019 23.771616144896726