Year	Cases per 100,000
1990	4.59
1991	4.61
1992	4.63
1993	4.66
1994	4.68
1995	4.7
1996	4.57
1997	4.44
1998	4.31
1999	4.19
2000	4.07
2001	4
2002	3.93
2003	3.86
2004	3.79
2005	3.73
2006	3.71
2007	3.69
2008	3.68
2009	3.66
2010	3.64
2011	3.71
2012	3.79
2013	3.86
2014	3.94
2015	4.01
2016	4.09
