Year	per 1,000 people
1960	0.215
1965	0.255
1970	0.24
1975	0.235
1980	0.521
1981	0.552
1985	0.529
1989	0.858
1990	0.811
1991	0.835
1992	0.847
1993	0.844
1994	0.845
1995	0.85
2000	0.888
2001	0.904
2002	0.961
2003	0.944
2004	1.042
2005	1.067
2006	1.107
2007	1.122
2008	1.137
2009	1.152
2010	1.169
2011	1.407
2012	1.336
2013	1.585
2014	1.88
2015	1.972
2016	2.14
2017	2.261
2018	1.849
2019	2.538
2020	2.658