Year Cases per 100,000 2000 16 2001 16 2002 10 2003 11 2004 14 2005 13 2006 18 2007 17 2008 21 2009 21 2010 16 2011 17 2012 20 2013 18 2014 18 2015 14 2016 16 2017 14 2018 18 2019 16 2020 16