Year	per 1000 people
1960	0.91
1965	1.378
1970	1.729
1990	2.538
1991	2.695
1992	2.618
1998	2.433
1999	2.54
2002	2.755
2008	2.884
2009	2.675
2010	2.764
2011	2.879
2012	3.061
2013	3.117
2014	3.196
2015	3.262