Year Cases per 100,000 1990 15.11 1991 15.79 1992 16.53 1993 17.32 1994 18.16 1995 19.06 1996 18.97 1997 18.88 1998 18.79 1999 18.7 2000 18.61 2001 18.36 2002 18.11 2003 17.86 2004 17.62 2005 17.39 2006 17.37 2007 17.35 2008 17.33 2009 17.31 2010 17.3 2011 17.39 2012 17.48 2013 17.58 2014 17.68 2015 17.78 2016 17.89