Year	per 1,000 people
1960	1
1961	1
1962	1
1963	1
1964	1
1965	1
1966	1
1967	1
1968	1
1969	1.1
1970	1.1
1971	1.1
1972	1.1
1973	1.1
1974	1.1
1975	1.1
1976	1.1
1977	1.2
1978	1.2
1979	1.2
1981	1.3
1985	1.5
1990	1.649
1992	1.702
1994	1.772
1996	1.841
1998	1.89
2000	1.935
2002	1.979
2004	2.031
2006	2.083
2008	2.147
2010	2.213
2012	2.284
2014	2.354
2016	2.426
2018	2.498
2020	2.614