Year	per 1,000 people
2000	4.22
2001	4.25
2002	4.2
2003	4.22
2004	4.21
2005	4.18
2006	4.21
2007	4.05
2008	3.93
2009	3.94
2010	3.98
2011	3.98
2012	3.97
2013	3.89
2014	3.93
2015	3.93
2016	3.93
2017	3.86