Year Cases per 100,000 1990 50.5 1991 55.4 1992 58.3 1993 61.3 1994 64.4 1995 67.6 1996 69.8 1997 73.1 1998 76.7 1999 80.6 2000 84.9 2001 88.5 2002 91.1 2003 91.2 2004 88.3 2005 83.7 2006 78.3 2007 74.4