Year	Cases per 100,000
1990	2.7
1991	3.3
1992	3.9
1993	4.5
1994	4.9
1995	5.3
1996	5.6
1997	5.8
1998	5.9
1999	6
2000	6.1
2001	6.2
2002	6.2
2003	6.3
2004	6.3
2005	6.3
2006	6.4
2007	6.5