Year Cases per 100,000 1990 49.3 1991 49.52 1992 51.28 1993 52.44 1994 53.56 1995 53.84 1996 53.37 1997 53.18 1998 52.46 1999 51.39 2000 51.14 2001 51.63 2002 52.55 2003 53.99 2004 55.4 2005 57.73 2006 58.51 2007 58.68 2008 58.62 2009 58.03 2010 57.76 2011 56.71 2012 55.77 2013 54.91 2014 53.43 2015 52.49 2016 51.74