Year	per 1,000 people
1960	0.065
1965	0.085
1970	0.114
1981	0.203
1985	0.27
1989	0.081
1990	0.078
1995	0.293
1999	0.297
2000	0.302
2004	0.376
2005	0.389
2006	0.426
2007	0.45
2008	0.487
2009	0.501
2010	0.535
2011	0.564
2012	0.594
2016	0.633
2017	0.882
2018	0.69
2019	0.751