Year % of population 2000 2 2001 2.2 2002 2.5 2003 2.9 2004 3.4 2005 3.9 2006 4.5 2007 5.4 2008 6.4 2009 7.6 2010 9.1 2011 10.9 2012 13.1 2013 15.3 2014 18 2015 20.9 2016 24.3 2017 27.9 2018 31.9 2019 36.1 2020 40.75 2021 45.9 2022 50.7