Year Cases per 100,000 1990 30 1991 49.1 1992 71.7 1993 94.6 1994 115 1995 128.4 1996 132.6 1997 138.9 1998 143.7 1999 146 2000 148.5 2001 144.6 2002 144.7 2003 142 2004 139.6 2005 134.2 2006 125.9 2007 117.7