Year per 1,000 people 1960 18.5 1961 18.4 1962 18.1 1963 18.2 1964 17.7 1965 17.1 1966 17 1967 16.8 1968 15.9 1969 14.6 1970 14 1971 13.2 1972 12.7 1973 12.2 1974 13.3 1975 13.9 1976 14.1 1977 13.9 1978 13.5 1979 13.3 1980 13.2 1981 13.2 1982 13.7 1983 13.8 1984 13.3 1985 12.8 1986 12.3 1987 12.1 1988 12.8 1989 12.8 1990 13.1 1991 13 1992 13.2 1993 12.8 1994 12.8 1995 12.3 1996 11.8 1997 11.5 1998 11.1 1999 11.1 2000 11 2001 10.8 2002 10.7 2003 10.9 2004 11 2005 11 2006 11.2 2007 11.1 2008 11.2 2009 11.3 2010 11.4 2011 11.1 2012 11 2013 10.7 2014 10.5 2015 10.1 2016 9.6 2017 9.1 2018 8.6 2019 8.3 2020 8.4 2021 9 2022 8.1