Year % of population 2000 19.1 2001 22.2 2002 21.7 2003 23 2004 24.3 2005 18.2 2006 27 2007 33 2008 30 2009 31.1 2010 34.2 2011 35.3 2012 36.4 2013 37.6 2014 38.8 2015 39.5 2016 41.2 2017 42.9 2018 43.6 2019 44.9 2020 45.4 2021 47.7 2022 49