Year	per 1000 people
1990	3.795
1991	3.902
1992	3.962
1993	4.031
1994	4.089
1995	4.09
1996	4.152
1997	4.206
1998	4.271
1999	4.33
2000	4.393
2001	4.376
2002	4.446
2003	4.489
2004	4.51
2005	4.541
2006	4.56
2007	4.603
2008	4.67
2009	4.731
2010	3.756
2011	3.838
2012	3.835
2013	3.824
2014	3.819
2015	3.872