Year per 1000 people 1960 1.405 1965 1.667 1970 1.863 1971 1.896 1972 1.985 1973 2.042 1974 2.102 1975 2.152 1976 2.205 1977 2.258 1978 2.321 1979 2.408 1980 2.46 1981 2.484 1982 2.588 1983 2.688 1984 2.759 1985 2.865 1986 2.953 1987 3.022 1988 3.09 1989 3.139 1990 3.17 1991 2.979 1992 3.166 1993 3.359 1994 3.327 1995 3.458 1996 3.539 1997 3.447 1998 3.449 2000 3.399 2003 3.562 2006 3.66 2007 3.665 2008 3.635 2010 3.775 2011 3.859 2012 3.916 2013 3.984 2014 3.999