Year | Value | 2021 | 9.2598740349001 | 2020 | 9.2274497649077 | 2019 | 9.5793900347925 | 2018 | 9.836567480998 | 2017 | 10.074579560287 | 2016 | 10.428366001365 | 2015 | 10.551624831248 | 2014 | 10.641960359229 | 2013 | 10.623359024273 | 2012 | 10.915522637347 | 2011 | 10.965737730215 | 2010 | 11.152652637477 | 2009 | 11.284031423373 | 2008 | 11.534808370481 | 2007 | 11.495107696972 | 2006 | 11.371878220794 | 2005 | 11.129687297124 | 2004 | 11.218144865834 | 2003 | 11.215541410567 | 2002 | 11.184094945686 | 2001 | 11.297206101846 | 2000 | 11.609856653094 | 1999 | 11.502244587491 | 1998 | 11.640630335683 | 1997 | 11.725596882519 | 1996 | 11.879309353791 | 1995 | 11.993206726026 | 1994 | 12.301277882973 | 1993 | 12.562858790164 | 1992 | 12.923336368553 | 1991 | 13.159907971214 | 1990 | 13.441210362843 | 1989 | 13.374653527663 | 1988 | 13.497873255494 | 1987 | 13.412853545441 | 1986 | 13.472274046231 | 1985 | 13.6477362231 | 1984 | 13.733600388041 | 1983 | 13.95753166441 | 1982 | 14.191681189957 | 1981 | 14.253417676354 | 1980 | 14.508090633878 | 1979 | 14.576336430862 | 1978 | 14.457378062207 | 1977 | 14.755634723866 | 1976 | 14.921943931761 | 1975 | 15.279017158635 | 1974 | 15.863862733115 | 1973 | 16.11047010886 | 1972 | 16.641852999583 | 1971 | 17.509729361139 | 1970 | 17.798475642896 | 1969 | 17.891092096616 | 1968 | 18.042840049653 | 1967 | 18.474814703137 | 1966 | 18.248162921362 | 1965 | 19.360997181118 | 1964 | 20.095473154868 | 1963 | 20.295331324949 | 1962 | 20.492120965375 | 1961 | 20.836298321164 | 1960 | 20.952840647764 |
|