Year	Cases per 100,000
1990	96.4
1991	148.8
1992	161.4
1993	173.9
1994	176.8
1995	180.9
1996	174.2
1997	172.7
1998	171.3
1999	165
2000	167.7
2001	171.4
2002	177.6
2003	175.7
2004	164.7
2005	152.7
2006	139.4
2007	127.5