Year Cases per 100,000 1990 4.49 1991 4.5 1992 4.52 1993 4.54 1994 4.56 1995 4.58 1996 4.61 1997 4.65 1998 4.69 1999 4.74 2000 4.78 2001 4.98 2002 5.2 2003 5.42 2004 5.66 2005 5.91 2006 6.07 2007 6.24 2008 6.42 2009 6.6 2010 6.8 2011 6.85 2012 6.92 2013 6.98 2014 7.05 2015 7.12 2016 7.2