Year | Value | 2024 | 61.162 | 2023 | 60.727 | 2022 | 60.297 | 2021 | 59.872 | 2020 | 59.453 | 2019 | 59.039 | 2018 | 58.632 | 2017 | 58.231 | 2016 | 57.837 | 2015 | 57.448 | 2014 | 57.067 | 2013 | 56.685 | 2012 | 56.303 | 2011 | 55.919 | 2010 | 55.535 | 2009 | 55.15 | 2008 | 54.765 | 2007 | 54.379 | 2006 | 53.992 | 2005 | 53.605 | 2004 | 53.218 | 2003 | 52.83 | 2002 | 52.441 | 2001 | 52.398 | 2000 | 52.638 | 1999 | 52.879 | 1998 | 53.12 | 1997 | 53.36 | 1996 | 53.6 | 1995 | 53.841 | 1994 | 54.08 | 1993 | 54.32 | 1992 | 54.559 | 1991 | 54.799 | 1990 | 55.038 | 1989 | 55.277 | 1988 | 55.208 | 1987 | 54.87 | 1986 | 54.532 | 1985 | 54.194 | 1984 | 53.855 | 1983 | 53.516 | 1982 | 53.176 | 1981 | 52.836 | 1980 | 52.497 | 1979 | 52.156 | 1978 | 51.747 | 1977 | 51.279 | 1976 | 50.812 | 1975 | 50.344 |
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