Year Cases per 100,000 1990 6.71 1991 6.72 1992 6.74 1993 6.75 1994 6.77 1995 6.79 1996 6.68 1997 6.59 1998 6.49 1999 6.4 2000 6.31 2001 6.16 2002 6.02 2003 5.88 2004 5.75 2005 5.62 2006 5.7 2007 5.78 2008 5.86 2009 5.95 2010 6.04 2011 5.99 2012 5.95 2013 5.91 2014 5.86 2015 5.82 2016 5.78