Year Cases per 100,000 1990 2.68 1991 2.77 1992 2.87 1993 2.98 1994 3.09 1995 3.2 1996 3.41 1997 3.63 1998 3.87 1999 4.12 2000 4.4 2001 4.46 2002 4.53 2003 4.6 2004 4.67 2005 4.75 2006 4.84 2007 4.92 2008 5.02 2009 5.11 2010 5.21 2011 5.22 2012 5.24 2013 5.26 2014 5.28 2015 5.3 2016 5.32