Year	Cases per 100,000
1990	1.1
1991	1.5
1992	2.1
1993	2.8
1994	3.5
1995	4.3
1996	4.9
1997	5.5
1998	5.8
1999	6
2000	6.1
2001	6.1
2002	6
2003	5.9
2004	5.7
2005	5.5
2006	5.4
2007	5.2