Year % of population 2000 20.5939673265979 2001 20.5472815173527 2002 20.5005931077099 2003 20.4536056364778 2004 20.40631886511 2005 19.9721489886999 2006 19.5450444000148 2007 19.1248922472729 2008 18.7110296424231 2009 18.3030851796557 2010 17.9009514050434 2011 17.504011935079 2012 17.1121604556915 2013 16.7250416362785 2014 16.3420826919898 2015 15.9631874719448 2016 15.5882420568199 2017 15.2164875035595 2018 14.847835432135 2019 14.4819824288711 2020 14.1186346735747 2021 13.7575067532956 2022 13.8462938417752