Year Cases per 100,000 1990 5.61 1991 5.68 1992 5.76 1993 5.84 1994 5.9 1995 5.98 1996 5.95 1997 5.92 1998 5.9 1999 5.92 2000 5.94 2001 6.02 2002 6.1 2003 6.19 2004 6.28 2005 6.37 2006 6.38 2007 6.39 2008 6.4 2009 6.41 2010 6.41 2011 6.38 2012 6.36 2013 6.33 2014 6.31 2015 6.29 2016 6.27