Year	Cases per 100,000
1968	5.46
1969	3.7
1970	3.85
1971	2.74
1972	5.21
1973	5.06
1974	2.85
1975	5.03
1976	2.7
1977	4.64
1978	4.2
1979	4.25
1980	5.94
1981	3.86
1982	4.85
1983	4.63
1984	4.5
1985	3.83
1986	5.78
1987	3.41
1988	3.63
1989	4.52
1990	5.19
1991	5.24
1992	5.3
1993	5.36
1994	5.42
1995	5.49
1996	5.51
1997	5.52
1998	5.55
1999	5.57
2000	5.59
2001	5.66
2002	5.74
2003	5.82
2004	5.9
2005	5.99
2006	6.12
2007	6.26
2008	6.41
2009	6.56
2010	6.72
2011	6.87
2012	7.03
2013	7.19
2014	7.36
2015	7.53
2016	7.71