Year % of people at risk 2003 0.4 2004 0.6 2005 0.4 2006 0.5 2007 0.5 2008 0.5 2009 0.6 2010 0.8 2011 0.9 2012 1.1 2013 1.4 2014 1.5 2015 1.3 2016 1.1 2017 0.8 2018 0.8 2019 0.7 2020 0.9 2021 0.7 2022 0.7