Year	Cases per 100,000
1990	7.98
1991	7.79
1992	7.65
1993	7.46
1994	7.28
1995	7.09
1996	6.84
1997	6.54
1998	6.26
1999	6.08
2000	5.95
2001	5.74
2002	5.53
2003	5.26
2004	4.96
2005	4.77
2006	4.58
2007	4.35
2008	4.22
2009	4.19
2010	4.19
2011	4.09
2012	4.03
2013	3.94
2014	3.86
2015	3.83
2016	3.81
