Year	per 1,000 people
1960	0.33512544631958
1980	1.62030005455017
1981	1.60759997367859
1989	2.50720000267029
1990	2.1087999344
1998	2.2000000477
2000	2.18
2001	2.1
2002	2.04
2003	2.04
2004	2.2
2005	2.1
2006	2.1
2007	2.02
2008	2.02
2009	1.9
2010	1.77
2011	1.77
2012	1.65
2013	1.71
2014	1.58
2015	1.56
2016	1.49
2017	1.47