Year Cases per 100,000 1990 5.4 1991 5.43 1992 5.51 1993 5.55 1994 5.62 1995 5.68 1996 5.98 1997 6.31 1998 6.7 1999 7.11 2000 7.61 2001 7.58 2002 7.55 2003 7.52 2004 7.5 2005 7.47 2006 7.38 2007 7.28 2008 7.19 2009 7.09 2010 7.01 2011 6.94 2012 6.87 2013 6.81 2014 6.75 2015 6.7 2016 6.66