Year Cases per 100,000 1990 9.51 1991 9.45 1992 9.39 1993 9.34 1994 9.29 1995 9.25 1996 9.23 1997 9.22 1998 9.21 1999 9.2 2000 9.2 2001 9.16 2002 9.13 2003 9.1 2004 9.07 2005 9.05 2006 9.05 2007 9.05 2008 9.05 2009 9.05 2010 9.06 2011 9.04 2012 9.03 2013 9.01 2014 9 2015 8.98 2016 8.98