Year	per 1000 people
1985	3.871
1986	3.939
1987	4.004
1988	4.04
1989	4.085
1990	4.07
1991	4.046
1992	3.872
1993	3.972
1994	3.835
1995	3.859
1996	4.096
1997	4.155
1998	4.209
1999	4.194
2001	4.172
2002	4
2003	4.252
2004	4
2005	4
2006	4.309
2010	5
2011	4.244
2012	4.031
2013	4.022
2014	4.163
2015	3.975