Year	Cases per 100,000
1990	13
1991	13
1992	13
1993	13
1994	13
1995	13
1996	13
1997	13
1998	13
1999	12
2000	12
2001	12
2002	12
2003	12
2004	12
2005	12
2006	12
2007	12
