Year Cases per 100,000 1990 9.35 1991 9.25 1992 9.16 1993 9.08 1994 9 1995 8.92 1996 8.97 1997 9.03 1998 9.09 1999 9.14 2000 9.21 2001 9.17 2002 9.14 2003 9.1 2004 9.07 2005 9.05 2006 8.92 2007 8.8 2008 8.68 2009 8.56 2010 8.46 2011 8.38 2012 8.3 2013 8.23 2014 8.16 2015 8.09 2016 8.02