Year	Cases per 100,000
1990	3.1
1991	4.1
1992	5.4
1993	6.9
1994	8.8
1995	10.9
1996	13.4
1997	16.3
1998	19.5
1999	23.1
2000	26.9
2001	30.9
2002	35
2003	39.2
2004	43.3
2005	47.5
2006	51.7
2007	55.5