Year Cases per 100,000 1990 9.85 1991 9.71 1992 9.57 1993 9.42 1994 9.27 1995 9.16 1996 8.99 1997 8.79 1998 8.58 1999 8.39 2000 8.2 2001 8.01 2002 7.85 2003 7.69 2004 7.54 2005 7.4 2006 7.25 2007 7.09 2008 6.94 2009 6.81 2010 6.7 2011 6.55 2012 6.45 2013 6.35 2014 6.24 2015 6.14 2016 6.05