Year	Cases per 100,000
1980	24
1981	29
1982	24
1983	22
1984	24
1985	23
1986	24
1987	22
1988	19
1989	18
1990	17
1991	21
1992	7
1993	17
1994	23
1995	36
1996	29
1997	33
1998	47
1999	48
2000	43
2001	45
2002	47
2003	51
2004	55
2005	73
2006	59
2007	56