Year	Cases per 100,000
1990	0.5
1991	0.6
1992	0.6
1993	0.8
1994	0.9
1995	1.2
1996	1.7
1997	2.4
1998	3.4
1999	4.3
2000	4.8
2001	5.5
2002	6.3
2003	7.6
2004	8.8
2005	10.4
2006	12
2007	13.7