Year	per 1,000 people
1970	0.033
1981	0.049
1982	0.065
1990	0.07
1991	0.19
1993	0.281
1996	0.656
2004	1
2007	1.698
2009	1.507
2010	1.452
2014	1.848
2016	1.288
2017	1.837
2018	1.799
2019	2.161