Year	Cases per 100,000
1990	10
1991	15
1992	21.4
1993	28.4
1994	34.9
1995	40.3
1996	44.5
1997	47.8
1998	50.4
1999	52.4
2000	53.9
2001	55.2
2002	56.2
2003	57.1
2004	57.9
2005	58.6
2006	59.4
2007	60.5