Year Cases per 100,000 1990 16.7 1991 16.83 1992 16.97 1993 17.11 1994 17.25 1995 17.39 1996 17.62 1997 17.85 1998 18.09 1999 18.33 2000 18.58 2001 19.27 2002 19.98 2003 20.73 2004 21.5 2005 22.31 2006 22.26 2007 22.2 2008 22.15 2009 22.1 2010 22.06 2011 22.08 2012 22.11 2013 22.14 2014 22.16 2015 22.19 2016 22.23