Year	Cases per 100,000
1990	11.6
1991	19.3
1992	30.1
1993	46
1994	68.4
1995	97
1996	131
1997	168.8
1998	208
1999	264.8
2000	312.4
2001	361.1
2002	394.4
2003	428.7
2004	450.4
2005	457.2
2006	469.1
2007	481