Year	per 100,000 population
2000	4.7
2001	4.3
2002	4.4
2003	4.2
2004	4
2005	4.5
2006	4.3
2007	4.2
2008	4
2009	3.9
2010	3.9
2011	3.7
2012	3.6
2013	3.6
2014	3.5
2015	3.4
2016	3.5
2017	3.5
2018	3.4
2019	3.3