Year	Cases per 100,000
1990	295.1
1991	278.9
1992	350.5
1993	384.3
1994	475
1995	627
1996	837
1997	658.8
1998	926.3
1999	614.2
2000	378.4
2001	1448
2002	1588
2003	1792
2004	1813
2005	2200
2006	2230