Year	per 1,000 people
1980	2.06
1981	2.218
1982	2.181
1983	2.247
1984	2.166
1985	2.287
1986	2.399
1987	2.519
1988	2.538
1989	2.423
2011	4.769
2012	4.955
2013	4.925
2014	6.018