Year Cases per 100,000 1990 16.56 1991 16.3 1992 16.38 1993 16.1 1994 15.77 1995 15.75 1996 15.43 1997 14.83 1998 14.59 1999 14.78 2000 15.3 2001 14.66 2002 13.96 2003 13.8 2004 13.53 2005 13.33 2006 13.4 2007 12.94 2008 13 2009 13.05 2010 13.01 2011 12.87 2012 12.64 2013 12.28 2014 12.58 2015 12.37 2016 12.28