Year	Cases per 100,000
1990	12
1991	10
1992	10
1993	8
1994	8
1995	9
1996	9
1997	8
1998	9
1999	8
2000	8
2001	9
2002	9
2003	10
2004	8
2005	8
2006	9
2007	6
