Year	per 1,000 people
1960	1.405
1965	1.667
1970	1.863
1971	1.896
1972	1.985
1973	2.042
1974	2.102
1975	2.152
1976	2.205
1977	2.258
1978	2.321
1979	2.408
1980	2.46
1981	2.484
1982	2.588
1983	2.688
1984	2.759
1985	2.865
1986	2.953
1987	3.022
1990	3.25
1991	3.068
1992	3.119
1993	3.305
1994	3.286
1995	3.429
1996	3.522
1997	3.445
1998	3.458
2000	3.399
2001	3.384
2002	3.472
2003	3.553
2004	3.484
2005	3.605
2006	3.617
2007	3.612
2008	3.577
2009	3.661
2010	3.683
2011	3.763
2012	3.819
2013	3.888
2014	3.907
2015	3.973
2018	4.168