Year Cases per 100,000 1990 5.5 1991 5.5 1992 5.5 1993 5.52 1994 5.54 1995 5.57 1996 5.57 1997 5.57 1998 5.59 1999 5.64 2000 5.68 2001 5.72 2002 5.75 2003 5.78 2004 5.8 2005 5.83 2006 5.87 2007 5.9 2008 5.94 2009 5.97 2010 6.01 2011 6.05 2012 6.09 2013 6.09 2014 6.08 2015 6.08 2016 6.08