Year Cases per 100,000 1990 24.3 1991 27.2 1992 29 1993 30.8 1994 32.7 1995 35.3 1996 38.2 1997 42.7 1998 47.8 1999 53.1 2000 58.3 2001 62.5 2002 65.5 2003 66.4 2004 64.9 2005 62 2006 58.4 2007 55.4