Year	Cases per 100,000
1990	1.8
1991	2.9
1992	3.2
1993	4.9
1994	6.4
1995	8.7
1996	9.7
1997	9.5
1998	9.9
1999	9.7
2000	10.4
2001	11.7
2002	13.3
2003	14.7
2004	15.1
2005	15.7
2006	15.7
2007	15.8