Year	per 1,000 people
1971	33.6
1972	30.8
1973	28.8
1974	32.1
1975	30.5
1976	27.1
1977	25.9
1978	28.9
1979	27.6
1980	28.9
1981	28.1
1982	24.1
1983	25.8
1984	26.9
1985	26.5
1986	26.2
1987	24.5
1988	23.8
1989	23
1990	23.1
1991	24.2
1992	22.6
1993	23.4
1994	22.9
1995	21
1996	21.1
1997	19.1
1998	17.9
1999	18.2
2000	18.6
2001	17.7
2002	17.7
2003	18.1
2004	17.4
2005	18.5
2006	17.3
2007	17.6
2008	17.8
2009	18.1
2010	16.8
2011	18.6
2012	18.6
2013	17.4
2014	17
2015	17
2016	17.4
2017	17.2
2018	17.1
2019	16.4
2020	15.8
2021	16.8
2022	13.1