Year Cases per 100,000 2000 11 2001 8.5 2002 8.5 2003 8.6 2004 7.6 2005 7 2006 6.3 2007 5.7 2008 5.1 2009 5.2 2010 5 2011 5 2012 5 2013 5.2 2014 5.3 2015 6.9 2016 7 2017 6.5 2018 6.3 2019 5.5 2020 4.8