Year	Cases per 100,000
1990	8.03
1991	7.88
1992	7.76
1993	7.67
1994	7.57
1995	7.49
1996	7.36
1997	7.21
1998	7.02
1999	6.73
2000	6.48
2001	6.23
2002	6.05
2003	5.92
2004	5.79
2005	5.66
2006	5.51
2007	5.21
2008	4.97
2009	4.87
2010	4.99
2011	4.74
2012	4.53
2013	4.42
2014	4.32
2015	4.23
2016	4.15