Year Cases per 100,000 1990 18.33 1991 18.4 1992 18.62 1993 18.61 1994 18.37 1995 17.61 1996 16.94 1997 16.52 1998 16.46 1999 15.76 2000 15.29 2001 15.02 2002 14.73 2003 14.36 2004 13.71 2005 13.52 2006 13.14 2007 12.69 2008 12.23 2009 11.77 2010 11.26 2011 11.02 2012 10.67 2013 10.52 2014 10.35 2015 10.43 2016 10.45