Year Cases per 100,000 2000 25 2001 13 2002 18 2003 15 2004 19 2005 13 2006 14 2008 6.5 2009 8.7 2010 7.5 2011 11 2012 12 2013 12 2014 12 2015 9.8 2016 6.7 2017 15 2018 5.6 2019 9.1 2020 6.6