Year	per 1,000 people
1960	5.5746922492981
1970	4.76300001144409
1975	4.97279977798462
1985	3.49200010299683
1993	3.0999999046
1995	3.1
1996	3.8699998856
2001	2.9
2005	2.8
2006	2.5
2007	1.9
2009	2
2014	1.72
2016	1.71