Year	Cases per 100,000
1980	13
1981	9
1982	9
1983	8
1984	7
1985	6
1986	3
1987	4
1988	4
1989	7
1990	3
1991	4
1992	4
1995	3
1996	1
1998	1
2000	3
2001	2
2003	1
2004	1
2005	1
2006	1
2007	1