Year | Value | 2022 | 37.592 | 2021 | 36.939 | 2020 | 36.29 | 2019 | 35.645 | 2018 | 35.004 | 2017 | 34.368 | 2016 | 33.736 | 2015 | 33.108 | 2014 | 32.487 | 2013 | 31.872 | 2012 | 31.264 | 2011 | 30.66 | 2010 | 30.064 | 2009 | 29.475 | 2008 | 28.893 | 2007 | 28.316 | 2006 | 27.748 | 2005 | 27.186 | 2004 | 26.242 | 2003 | 25.126 | 2002 | 24.044 | 2001 | 22.993 | 2000 | 21.977 | 1999 | 20.991 | 1998 | 20.039 | 1997 | 19.12 | 1996 | 18.234 | 1995 | 17.378 | 1994 | 16.854 | 1993 | 16.49 | 1992 | 16.133 | 1991 | 15.782 | 1990 | 15.437 | 1989 | 15.098 | 1988 | 14.766 | 1987 | 14.439 | 1986 | 14.118 | 1985 | 13.804 | 1984 | 13.504 | 1983 | 13.214 | 1982 | 12.93 | 1981 | 12.65 | 1980 | 12.377 | 1979 | 12.107 | 1978 | 11.843 | 1977 | 11.584 | 1976 | 11.331 | 1975 | 11.081 | 1974 | 10.837 | 1973 | 10.597 | 1972 | 10.295 | 1971 | 9.955 | 1970 | 9.625 | 1969 | 9.304 | 1968 | 8.994 | 1967 | 8.692 | 1966 | 8.4 | 1965 | 8.323 | 1964 | 8.246 | 1963 | 8.17 | 1962 | 8.095 | 1961 | 8.02 | 1960 | 7.946 |
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