Year Cases per 100,000 1990 5.78 1991 5.83 1992 5.88 1993 5.94 1994 6 1995 6.07 1996 6.09 1997 6.12 1998 6.15 1999 6.19 2000 6.23 2001 6.23 2002 6.23 2003 6.24 2004 6.25 2005 6.26 2006 6.24 2007 6.22 2008 6.21 2009 6.19 2010 6.19 2011 6.19 2012 6.19 2013 6.2 2014 6.21 2015 6.22 2016 6.23