Year	per 1000 people
1960	0.187
1970	0.243
1975	0.242
1980	0.326
1981	0.387
1984	0.352
1988	0.647
1990	0.84
1993	0.66
1995	0.91
1997	1.071
1999	1.258
2000	1.211
2002	1.351
2005	1.741
2006	1.5
2008	1.922
2010	1.596