Year	Cases per 100,000
1990	17.72
1991	17.6
1992	17.48
1993	17.47
1994	17.48
1995	17.69
1996	17.38
1997	16.87
1998	16.38
1999	15.46
2000	14.95
2001	13.82
2002	13.16
2003	12.6
2004	12.22
2005	11.93
2006	11.48
2007	11.12
2008	10.77
2009	10.43
2010	10.27
2011	10.14
2012	10.02
2013	9.89
2014	9.77
2015	9.69
2016	9.63