Year	per 1000 people
1960	2.472
1965	2.5
1970	2.881
1971	2.974
1972	3.156
1973	3.304
1979	2.694
1980	3.094
1981	3.167
1982	3.214
1983	3.323
1984	3.353
1985	3.215
1986	3.2
1987	3.207
1988	3.21
1989	3.195
1990	3.207
1991	3.303
1992	3.657
1993	3.696
1994	3.731
1995	4.857
1996	3.766
1997	3.793
1998	3.775
1999	3.915
2000	3.766
2001	3.91
2003	3.82
2006	3.67
2007	3.633
2010	3.414
2011	3.345
2012	3.344
2013	3.539
2014	3.619
2015	3.576