Year Cases per 100,000 1990 19.04 1991 19.04 1992 19.06 1993 19.09 1994 19.12 1995 19.16 1996 19.04 1997 18.95 1998 18.86 1999 18.78 2000 18.72 2001 18.37 2002 18.05 2003 17.74 2004 17.44 2005 17.16 2006 16.78 2007 16.4 2008 16.05 2009 15.71 2010 15.4 2011 15.41 2012 15.44 2013 15.48 2014 15.54 2015 15.61 2016 15.7