Year Cases per 100,000 1990 3.1 1991 3.14 1992 3.18 1993 3.23 1994 3.27 1995 3.32 1996 3.33 1997 3.33 1998 3.34 1999 3.35 2000 3.36 2001 3.44 2002 3.53 2003 3.62 2004 3.71 2005 3.81 2006 3.9 2007 4 2008 4.11 2009 4.21 2010 4.32 2011 4.35 2012 4.38 2013 4.41 2014 4.44 2015 4.48 2016 4.51