Year	Cases per 100,000
1990	10.2
1991	10.45
1992	10.72
1993	10.95
1994	11.19
1995	11.45
1996	10.91
1997	10.34
1998	9.7
1999	8.84
2000	8.84
2001	8.77
2002	8.74
2003	8.65
2004	8.53
2005	8.42
2006	8.46
2007	8.5
2008	8.55
2009	8.58
2010	8.6
2011	8.64
2012	8.58
2013	8.51
2014	8.43
2015	8.41
2016	8.38