Year	Cases per 100,000
1990	69.5
1991	102.4
1992	138.2
1993	177.8
1994	217.4
1995	256
1996	289
1997	324.7
1998	360.7
1999	398.5
2000	439.2
2001	477.7
2002	511.7
2003	533.5
2004	537.9
2005	529.8
2006	514.8
2007	500.3