Year	per 1,000 people
1960	0.267
1965	0.311
1970	0.509
1975	0.49
1981	0.523
1984	0.697
1990	0.45
1993	0.426
1995	0.34
2001	1.181
2007	0.326
2010	0.431
2011	0.459
2016	1.558
2017	1.008