Year Cases per 100,000 2000 18 2001 22 2002 18 2003 23 2004 16 2005 16 2006 14 2007 11 2008 13 2009 17 2010 22 2011 25 2012 24 2013 29 2014 44 2015 42 2016 36 2017 41 2018 44 2019 53 2020 48