Year Cases per 100,000 2000 69 2001 56 2002 53 2003 62 2004 57 2005 56 2006 54 2007 56 2008 54 2009 56 2010 54 2011 50 2012 51 2013 47 2014 41 2015 40 2016 34 2017 29 2018 25 2019 23 2020 16