Year | Value | 2021 | 84.6 | 2020 | 84.8 | 2019 | 84.7 | 2018 | 84.8 | 2017 | 84.6 | 2016 | 84.2 | 2015 | 84.1 | 2014 | 84.1 | 2013 | 83.9 | 2012 | 83.6 | 2011 | 83.5 | 2010 | 83.6 | 2009 | 83.3 | 2008 | 83 | 2007 | 82.4 | 2006 | 82.5 | 2005 | 82.2 | 2004 | 82.4 | 2003 | 81.8 | 2002 | 81.5 | 2001 | 81.2 | 2000 | 80.9 | 1999 | 80.4 | 1998 | 80.3 | 1997 | 80.1 | 1996 | 80 | 1995 | 79.5 | 1994 | 79.4 | 1993 | 79.1 | 1992 | 78.4 | 1991 | 78.5 | 1990 | 78.4 | 1989 | 78.1 | 1988 | 75 | 1987 | 77 | 1986 | 76.8 | 1985 | 77 | 1984 | 76.6 | 1983 | 76.2 | 1982 | 75.8 | 1981 | 75.9 | 1980 | 75.74 | 1979 | 75.3 | 1978 | 75 | 1977 | 74.7 | 1976 | 74.8 | 1975 | 73.93 | 1974 | 73.27 | 1973 | 73.23 | 1972 | 72 | 1971 | 73.44 | 1970 | 72.96 | 1969 | 72.84 | 1968 | 72.88 | 1967 | 73.2 | 1966 | 73.73 | 1962 | 73.7 | 1961 | 73.62 |
|