Year	Cases per 100,000
1990	0
1991	0
1992	0
1993	0
1994	0
1995	0
1996	0.1
1997	0.1
1998	0.2
1999	0.3
2000	0.5
2001	0.7
2002	0.8
2003	0.9
2004	1.1
2005	1.1
2006	1.2
2007	1.3