Year	Cases per 100,000
1968	6.94
1969	7.48
1970	6.66
1971	6.2265
1972	6.883
1973	6.0595
1974	6.166
1975	7.0425
1976	6.899
1977	6.5155
1978	8.222
1979	8.6585
1980	8.165
1981	8.6515
1982	9.228
1983	10.3545
1984	10.851
1985	10.7075
1986	10.194
1987	10.7105
1988	11.217
1989	11.4635
1990	11.02
1991	11.01
1992	10.98
1993	10.94
1994	10.96
1995	10.9
1996	10.85
1997	10.91
1998	10.93
1999	11.03
2000	11.21
2001	11.45
2002	11.77
2003	12.19
2004	12.59
2005	13.01
2006	13.52
2007	14.18
2008	14.9
2009	15.49
2010	15.97
2011	16.19
2012	16.31
2013	16.36
2014	16.31
2015	16.2
2016	16.12
