Year	per 100,000 population
2000	19.1
2001	18.9
2002	19.1
2003	19
2004	18.6
2005	18.2
2006	19.2
2007	19.1
2008	18.9
2009	19.8
2010	19.5
2011	19
2012	19.1
2013	18.9
2014	18.2
2015	18.2
2016	18
2017	18.1
2018	18.1
2019	18