Year	per 1,000 people
1960	0.9226457420432216
1970	0.9616808724164598
1975	0.8868961256254669
1980	1.0348816061569892
1985	1.1039620415433506
1991	1.0884367360856764
2000	1.0584038055670157
2001	0.9163644046431813
2002	0.9389462704059592
2003	1.1887471658519109
2005	0.9345906060415814
2006	0.942885530684248
2007	0.9492558190424318
2008	0.8667807698193943
2009	0.8391112504539326
2010	0.9558484998792803
2011	1.1396318921270876
2012	0.90943253649479
2013	0.9298023509898891
2014	0.9503553854647245
2015	0.9198550855923021
2016	0.8724901172678462
2017	0.9217807014113057