Year Cases per 100,000 1990 41.03 1991 41.86 1992 42.76 1993 43.68 1994 44.62 1995 45.62 1996 45.3 1997 45.03 1998 44.75 1999 44.49 2000 44.27 2001 42.8 2002 41.41 2003 40.08 2004 38.8 2005 37.6 2006 36.67 2007 35.74 2008 34.87 2009 34.03 2010 33.24 2011 32.64 2012 32.08 2013 31.54 2014 31.01 2015 30.49 2016 30