Year per 1000 people 1960 1.1 1965 1.2 1970 1.2 1975 1.3 1976 1.3 1977 1.3 1978 1.4 1979 1.4 1980 1.5 1981 1.5 1982 1.6 1983 1.6 1985 1.7 1986 1.7 1987 1.8 1988 1.8 1989 1.8 1990 1.8 1991 1.9 1992 1.9 1993 1.9 1995 2.428 1996 2 1997 2.1 1998 2.1 1999 2.2 2000 2.583 2001 2.2 2002 2.3 2004 2.704 2006 2.402 2007 2.41 2008 2.416 2009 2.422 2010 2.429 2011 2.458 2012 2.492 2013 2.554 2014 2.568