Year	per 1000 people
1961	1.1
1966	1.1
1971	1.1
1973	1.2
1976	1.3
1977	1.4
1978	1.4
1979	1.5
1980	1.6
1981	1.6
1982	1.6
1983	1.7
1984	1.7
1985	1.7
1986	1.8
1987	1.8
1988	1.9
1989	1.9
1990	1.9
1991	1.9
1992	1.9
1993	1.9
1994	2
1995	2
1996	2
1997	2.2
1998	2.2
1999	2.2
2001	2.311
2002	2.067
2003	2.2
2007	2.302
2008	2.547
2009	2.679
2010	2.612
2011	2.641
2012	2.698
2013	2.818
2014	2.852
2015	3.061