Year	per 1,000 people
1960	0.011
1965	0.016
1970	0.017
1975	0.016
1984	0.025
1990	0.018
1992	0.027
1994	0.023
1996	0.024
1997	0.035
1998	0.033
2002	0.033
2004	0.022
2008	0.019
2009	0.027
2012	0.053
2013	0.051
2014	0.027
2015	0.032
2016	0.033
2017	0.022
2018	0.036
2019	0.038
2020	0.034