Year Cases per 100,000 1990 23.16 1991 24.53 1992 25.99 1993 27.55 1994 29.21 1995 30.98 1996 31.81 1997 32.67 1998 33.55 1999 34.47 2000 35.41 2001 34.98 2002 34.56 2003 34.15 2004 33.74 2005 33.34 2006 32.96 2007 32.59 2008 32.22 2009 31.86 2010 31.51 2011 31.11 2012 30.72 2013 30.34 2014 29.96 2015 29.59 2016 29.23