Year Cases per 100,000 1990 9.92 1991 9.82 1992 9.81 1993 9.77 1994 9.72 1995 9.62 1996 9.19 1997 8.79 1998 8.44 1999 8 2000 7.75 2001 7.68 2002 7.74 2003 7.82 2004 7.82 2005 7.8 2006 7.77 2007 7.72 2008 7.61 2009 7.46 2010 7.35 2011 7.29 2012 7.2 2013 7.16 2014 7.21 2015 6.99 2016 6.75