Year	Cases per 100,000
1968	11.29
1969	13.53
1970	12.18
1971	13.921
1972	10.972
1973	14.873
1974	16.044
1975	16.565
1976	18.276
1977	17.057
1978	20.238
1979	19.929
1980	21.56
1981	22.831
1982	23.142
1983	24.633
1984	24.084
1985	28.855
1986	26.836
1987	25.127
1988	29.638
1989	26.399
1990	28.38
1991	28.96
1992	29.57
1993	30.19
1994	30.82
1995	31.49
1996	31.42
1997	31.36
1998	31.3
1999	31.25
2000	31.21
2001	31.4
2002	31.6
2003	31.81
2004	32.03
2005	32.25
2006	31.66
2007	31.08
2008	30.53
2009	30
2010	29.5
2011	29.77
2012	30.05
2013	30.34
2014	30.64
2015	30.93
2016	31.25