Year	Cases per 100,000
1990	1.3
1991	2
1992	3
1993	4.4
1994	6
1995	7.7
1996	9.3
1997	10.6
1998	11.7
1999	12.5
2000	13
2001	13.5
2002	13.8
2003	13.9
2004	14.1
2005	14.1
2006	14.2
2007	14.4