Year	Cases per 100,000
1990	8.2
1991	11.4
1992	13.4
1993	14.8
1994	15.6
1995	15.9
1996	15.9
1997	15.6
1998	15.3
1999	14.8
2000	14.2
2001	13.6
2002	13
2003	12.6
2004	12.4
2005	12.3
2006	12.1
2007	12.1