Year	Cases per 100,000
1990	33
1991	31
1992	30
1993	29
1994	28
1995	27
1996	26
1997	25
1998	24
1999	23
2000	22
2001	21
2002	20
2003	20
2004	19
2005	18
2006	17
2007	17
