Year | Value | 2022 | 38.766 | 2021 | 38.052 | 2020 | 37.34 | 2019 | 36.628 | 2018 | 35.919 | 2017 | 35.213 | 2016 | 34.51 | 2015 | 33.809 | 2014 | 33.115 | 2013 | 32.429 | 2012 | 31.752 | 2011 | 31.08 | 2010 | 30.417 | 2009 | 29.762 | 2008 | 29.128 | 2007 | 28.504 | 2006 | 27.888 | 2005 | 27.281 | 2004 | 26.683 | 2003 | 26.092 | 2002 | 25.511 | 2001 | 24.937 | 2000 | 24.374 | 1999 | 23.817 | 1998 | 23.371 | 1997 | 22.965 | 1996 | 22.563 | 1995 | 22.166 | 1994 | 21.774 | 1993 | 21.387 | 1992 | 21.006 | 1991 | 20.629 | 1990 | 20.257 | 1989 | 19.891 | 1988 | 19.752 | 1987 | 19.688 | 1986 | 19.625 | 1985 | 19.561 | 1984 | 19.498 | 1983 | 19.435 | 1982 | 19.372 | 1981 | 19.309 | 1980 | 19.247 | 1979 | 19.175 | 1978 | 19.076 | 1977 | 18.978 | 1976 | 18.88 | 1975 | 18.782 | 1974 | 18.685 | 1973 | 18.588 | 1972 | 18.492 | 1971 | 18.396 | 1970 | 18.3 | 1969 | 17.911 | 1968 | 17.529 | 1967 | 17.153 | 1966 | 16.784 | 1965 | 16.421 | 1964 | 16.064 | 1963 | 15.714 | 1962 | 15.369 | 1961 | 15.031 | 1960 | 14.7 |
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