Year Cases per 100,000 1990 6.81 1991 6.7 1992 6.99 1993 7.49 1994 7.83 1995 7.72 1996 7.38 1997 7.3 1998 7.35 1999 7.44 2000 7.68 2001 7.57 2002 7.48 2003 7.22 2004 7.02 2005 6.52 2006 6.13 2007 5.71 2008 5.29 2009 5.01 2010 4.79 2011 4.6 2012 4.45 2013 4.37 2014 4.29 2015 4.19 2016 4.12