Year Cases per 100,000 1990 7.4 1991 10.5 1992 14.1 1993 18.5 1994 23.5 1995 29.3 1996 35.2 1997 42.1 1998 49.4 1999 57.2 2000 65.6 2001 73.5 2002 80.6 2003 85.4 2004 87 2005 86.3 2006 84.1 2007 82