Year Cases per 100,000 1990 3.64 1991 3.73 1992 3.83 1993 3.93 1994 4.03 1995 4.14 1996 4.17 1997 4.2 1998 4.23 1999 4.27 2000 4.3 2001 4.32 2002 4.33 2003 4.35 2004 4.36 2005 4.38 2006 4.38 2007 4.38 2008 4.38 2009 4.38 2010 4.38 2011 4.4 2012 4.41 2013 4.43 2014 4.44 2015 4.46 2016 4.47