Year	Cases per 100,000
1990	19.94
1991	20.12
1992	20.3
1993	20.48
1994	20.67
1995	20.86
1996	19.59
1997	18.4
1998	17.29
1999	16.25
2000	15.27
2001	15.62
2002	15.97
2003	16.34
2004	16.72
2005	17.11
2006	17.49
2007	17.88
2008	18.28
2009	18.69
2010	19.13
2011	18.98
2012	18.83
2013	18.69
2014	18.55
2015	18.42
2016	18.29