Year	per 1,000 people
1960	0.740457057952881
1970	0.654600024223328
1975	0.818300008773804
1985	0.556800007820129
1989	0.702600002288818
1990	0.665199995
1991	0.6686000228
1992	0.6650000215
1993	0.6575999856
1994	0.6600999832
1998	0.6
2002	0.6
2009	0.59
2010	0.57
2011	0.62
2012	0.83
2013	0.99
2014	0.94
2015	0.98
2016	0.99
2017	1.04