Year	per 1,000 people
1960	9.9
1962	7.4
1966	7.2
1970	7.6
1971	8.2
1972	7.3
1973	6.8
1974	6.3
1975	7.1
1976	6.8
1977	6.6
1978	6
1979	6.6
1980	7.3
1984	7.1
1989	7.7
1990	7.3
1991	7.7
1992	7.9
1993	8.2
1994	8.1
1995	7.9
1996	6.9
2000	8
2001	7.2
2002	6.7
2003	7.2
2004	6.8
2005	7.1
2006	7.1
2007	7
2008	6.8
2009	7.2
2010	7.4
2011	6.8
2012	6.8
2013	7.6
2014	7.8
2015	7.7
2016	7.7
2017	7.5
2018	8.3
2019	8.4
2020	8.8
2021	11.3
2022	9.1