Year per 1,000 people 1960 21.7 1961 21.2 1962 21.1 1963 21.4 1964 22 1965 21.1 1966 20.7 1967 20.7 1968 20.1 1969 19.9 1970 19.5 1971 19.6 1972 19.4 1973 19.2 1974 19.5 1975 18.7 1976 18.7 1977 18 1978 17.3 1979 16.2 1980 15.2 1981 14.1 1982 13.6 1983 12.7 1984 12.3 1985 11.9 1986 11.4 1987 11 1988 10.8 1989 10.5 1990 10.3 1991 10.2 1992 10.1 1993 9.8 1994 9.4 1995 9.1 1996 9.1 1997 9.2 1998 9.1 1999 9.4 2000 9.8 2001 9.9 2002 10.1 2003 10.4 2004 10.6 2005 10.6 2006 10.8 2007 10.9 2008 11.3 2009 10.6 2010 10.4 2011 10.1 2012 9.7 2013 9.1 2014 9.2 2015 9 2016 8.8 2017 8.4 2018 7.9 2019 7.6 2020 7.2 2021 7.1 2022 6.9