Year per 1000 people 1980 1.8 1981 1.8 1982 2 1983 2.1 1984 2.3 1985 2.3 1986 2.3 1987 2.3 1988 2.4 1989 2.5 1990 2.5 1991 2.4 1992 2.6 1993 2.6 1994 2.898 1995 2.903 1996 2.6 1997 2.916 1998 2.8 2001 3.66 2002 2.925 2003 3.001 2004 3.045 2005 3.202 2006 3.163 2007 3.419 2008 3.395 2009 3.403 2010 3.582 2011 3.622 2012 3.652 2013 3.648 2014 3.655