Year Cases per 100,000 1990 2.35 1991 2.44 1992 2.54 1993 2.64 1994 2.75 1995 2.86 1996 2.98 1997 3.11 1998 3.24 1999 3.38 2000 3.53 2001 3.73 2002 3.94 2003 4.17 2004 4.41 2005 4.67 2006 4.9 2007 5.13 2008 5.38 2009 5.65 2010 5.92 2011 6.06 2012 6.21 2013 6.36 2014 6.51 2015 6.67 2016 6.84