Year % of population 2007 0.8 2008 1.3 2009 3 2010 1.5 2011 2.8 2012 3.3 2013 3.8 2014 4.3 2015 4.8 2016 5.3 2017 4.2 2018 6.3 2019 6.8 2020 7.3 2021 7.7 2022 8.4