Year Cases per 100,000 1990 16.22 1991 15.99 1992 16.61 1993 19.01 1994 20.26 1995 19.11 1996 17.52 1997 16.27 1998 15.87 1999 16.65 2000 16.93 2001 16.93 2002 17.16 2003 17.51 2004 17.51 2005 17.84 2006 17.08 2007 16.95 2008 17.21 2009 16.76 2010 16.87 2011 16.65 2012 16.3 2013 16.15 2014 16.08 2015 15.89 2016 16.01