Year | Value | 2021 | 78.3 | 2020 | 80.4 | 2019 | 81.2 | 2018 | 80.8 | 2017 | 80.7 | 2016 | 80.7 | 2015 | 80.2 | 2014 | 80.5 | 2013 | 80.1 | 2012 | 79.9 | 2011 | 79.8 | 2010 | 78.8 | 2009 | 78.7 | 2008 | 78.7 | 2007 | 78.1 | 2006 | 78.2 | 2005 | 77.9 | 2004 | 77.8 | 2003 | 77.6 | 2002 | 77.6 | 2001 | 77.5 | 2000 | 77.2 | 1999 | 77 | 1998 | 76.7 | 1997 | 76.7 | 1996 | 76.7 | 1995 | 76.3 | 1994 | 76.5 | 1993 | 76.7 | 1992 | 76.2 | 1991 | 75.17 | 1990 | 75.44 | 1989 | 75.38 | 1988 | 75.5 | 1987 | 75.13 | 1986 | 74.75 | 1985 | 74.74 | 1984 | 74.91 | 1983 | 74.51 | 1982 | 74.72 | 1981 | 74.65 | 1980 | 74.25 | 1979 | 74.557 | 1978 | 74.125 | 1977 | 74.282 | 1976 | 74.088 | 1975 | 73.936 | 1974 | 73.699 | 1973 | 73.407 | 1972 | 73.838 | 1971 | 73.262 | 1970 | 72.922 | 1969 | 73.055 | 1968 | 73.45 | 1967 | 73.757 | 1966 | 73.173 | 1965 | 72.786 | 1964 | 73.482 | 1963 | 73.199 | 1962 | 72.652 | 1961 | 73.017 | 1960 | 72.526 |
|