Year	per 1,000 people
1960	1.2
1962	1.2
1963	1.1
1964	1.2
1965	1.3
1966	1.3
1967	1.3
1968	1.4
1969	1.4
1970	1.4
1971	1.5
1972	1.5
1973	1.6
1974	1.7
1975	1.7
1976	1.8
1977	1.9
1978	1.9
1979	1.9
1980	2
1981	2
1982	2.1
1983	2.1
1984	2.2
1985	2.2
1986	2.3
1987	2.5
1991	2.602
1992	2.656
1993	2.702
1994	2.785
1995	2.953
1996	3.047
1997	3.075
1998	3.166
1999	3.287
2000	3.38
2001	3.54
2002	3.218
2003	3.23
2004	3.4
2005	3.563
2006	3.731
2007	3.844
2008	3.955
2009	4.048
2010	4.114
2011	4.188
2012	4.231
2013	4.305
2014	4.429
2015	4.451
2016	4.581
2017	4.735
2018	4.857
2019	4.968
2020	5.086
2021	5.168