Year	Cases per 100,000
1990	5.72
1991	5.65
1992	5.58
1993	5.51
1994	5.44
1995	5.39
1996	5.2
1997	5.03
1998	4.86
1999	4.7
2000	4.55
2001	4.44
2002	4.34
2003	4.25
2004	4.16
2005	4.07
2006	4.03
2007	3.99
2008	3.94
2009	3.9
2010	3.87
2011	3.9
2012	3.93
2013	3.96
2014	3.99
2015	4.02
2016	4.06