Year	Cases per 100,000
1990	2539
1991	2041
1992	1988
1993	1496
1994	1418
1995	2103
1996	1468
1997	766.8
1998	409.4
1999	354.1
2000	1509
2001	29760
2002	28050
2003	28470
2004	31480
2005	29460
2006	27040