Year	Cases per 100,000
1990	4.16
1991	4.22
1992	4.26
1993	4.29
1994	4.26
1995	4.29
1996	4.36
1997	4.36
1998	4.23
1999	4.13
2000	4.12
2001	4
2002	4.02
2003	4.03
2004	3.99
2005	3.96
2006	3.93
2007	3.89
2008	3.88
2009	3.85
2010	3.92
2011	3.97
2012	3.83
2013	3.72
2014	3.64
2015	3.57
2016	3.49