Year	Cases per 100,000
1980	39
1981	35
1982	38
1983	44
1984	35
1985	34
1986	33
1987	30
1988	29
1989	30
1990	25
1991	25
1992	25
1993	30
1994	27
1995	27
1996	26
1998	24
1999	23
2000	21
2001	20
2002	19
2003	20
2004	20
2005	21
2006	21
2007	22