Year Cases per 100,000 1990 17.12 1991 16.48 1992 16.38 1993 16.19 1994 16.06 1995 16.22 1996 15.29 1997 14.3 1998 13.45 1999 12.77 2000 12.44 2001 11.93 2002 11.24 2003 10.88 2004 10.54 2005 10.22 2006 9.97 2007 9.76 2008 9.7 2009 9.52 2010 9.24 2011 9.29 2012 9.34 2013 9.42 2014 9.45 2015 9.47 2016 9.51