Year Cases per 100,000 1990 6.31 1991 6.31 1992 6.32 1993 6.33 1994 6.33 1995 6.35 1996 6.35 1997 6.36 1998 6.37 1999 6.37 2000 6.39 2001 6.36 2002 6.34 2003 6.32 2004 6.3 2005 6.29 2006 6.29 2007 6.29 2008 6.3 2009 6.31 2010 6.32 2011 6.32 2012 6.33 2013 6.33 2014 6.34 2015 6.34 2016 6.36