Year	Cases per 100,000
1980	64
1981	58
1982	49
1983	46
1984	46
1985	40
1986	36
1987	34
1988	31
1989	32
1990	29
1991	24
1992	22
1993	22
1994	21
1995	19
1996	22
1997	22
1998	20
1999	19
2000	19
2001	21
2002	16
2003	19
2004	22
2005	19
2006	17
2007	18