Year	Cases per 100,000
1990	20.86
1991	19.87
1992	19.61
1993	19.19
1994	18.94
1995	19.16
1996	19.22
1997	19.38
1998	19.64
1999	19.31
2000	19.01
2001	18.73
2002	18.47
2003	18.23
2004	18.01
2005	17.78
2006	17.53
2007	17.25
2008	17.01
2009	16.8
2010	16.62
2011	16.42
2012	16.21
2013	16.06
2014	15.9
2015	15.75
2016	15.61