Year	Cases per 100,000
1990	18.8
1991	19.52
1992	20.27
1993	21.04
1994	21.85
1995	22.7
1996	20.95
1997	19.35
1998	17.87
1999	16.51
2000	15.26
2001	15.16
2002	15.07
2003	14.98
2004	14.89
2005	14.81
2006	14.58
2007	14.36
2008	14.14
2009	13.94
2010	13.74
2011	13.88
2012	14.02
2013	14.16
2014	14.31
2015	14.45
2016	14.61