Year Cases per 100,000 2000 11 2001 10 2002 12 2003 12 2004 12 2005 14 2006 14 2007 13 2008 13 2009 13 2010 12 2011 13 2012 13 2013 11 2014 10 2015 8.9 2016 8.7 2017 7.9 2018 7.1 2019 7.1 2020 6.2