Year	Cases per 100,000
1990	20.3
1991	19.78
1992	19.18
1993	18.73
1994	18.1
1995	17.9
1996	17.52
1997	17.05
1998	16.71
1999	16.49
2000	16.04
2001	15.6
2002	15.15
2003	14.84
2004	14.38
2005	14.18
2006	13.66
2007	13.28
2008	12.92
2009	12.63
2010	12.26
2011	11.97
2012	11.76
2013	11.42
2014	11.15
2015	11
2016	10.87