Year per 1000 people 1960 0.8 1961 0.9 1962 0.9 1963 0.9 1964 0.9 1965 0.9 1966 0.9 1967 0.9 1968 0.9 1969 0.9 1970 0.9 1971 1 1972 1 1973 1.1 1974 1.1 1975 1.1 1976 1.2 1977 1.2 1978 1.2 1979 1.3 1980 1.3 1981 1.3 1982 1.3 1983 1.4 1984 1.4 1985 1.4 1986 1.4 1987 1.5 1988 1.5 1989 1.5 1990 1.6 1991 1.6 1992 1.6 1993 1.7 1994 1.7 1995 1.7 1996 1.8 1997 2.294 1998 1.9 1999 1.9 2000 1.9 2001 2 2002 2.3 2003 2.2 2010 2.697 2011 2.745 2012 2.757 2013 2.778 2014 2.806 2015 2.807 2016 2.825