Year	per 100,000 population
2000	4.2
2001	4.2
2002	4.2
2003	4.2
2004	4.2
2005	4
2006	4
2007	4
2008	3.9
2009	4.3
2010	4.6
2011	4.5
2012	4.5
2013	4.6
2014	4.6
2015	4.6
2016	4.1
2017	4.2
2018	4
2019	3.8