Year	Cases per 100,000
1990	21.49
1991	19.89
1992	20.22
1993	19.81
1994	18.98
1995	17.93
1996	17.93
1997	17.36
1998	16.43
1999	15.61
2000	15.58
2001	15.64
2002	14.86
2003	14.7
2004	14.05
2005	14.09
2006	14.29
2007	14.03
2008	13.9
2009	13.12
2010	12.7
2011	12.34
2012	12.09
2013	11.59
2014	11.64
2015	11.58
2016	11.56
