Year	per 1,000 people
1970	3.0677412178818004
1975	2.394949870093818
1980	3.5861761858786134
1985	4.119834834808141
1990	3.637435737238747
1991	3.420469700097152
2000	2.900103808660582
2001	2.7688524694834404
2002	2.6695183317495834
2003	2.8912087225110534
2005	2.6314777326516117
2006	2.671372139023706
2007	2.6764825264323626
2008	2.6531411765808373
2009	2.6070734818357097
2010	2.620048315486319
2011	2.684081981326432
2012	2.779118602254398
2013	2.8165250023451853
2014	2.7680186576474575
2015	2.6940391653802838
2016	2.726510787134067
2017	2.8817914877128024