Year	per 1000 people
1992	2
1993	2
1994	2
1995	2.1
1996	2.1
1997	2.1
1998	2.2
1999	2.3
2000	2.2
2001	2.4
2002	2.4
2003	2.6
2004	2.786
2006	2.94
2007	3.08
2008	3.187
2011	2.625
2012	2.667
2013	2.647
2014	2.777
2015	2.868
2016	2.961