Year | Value | 2024 | 49.141036852443 | 2023 | 49.133689430054 | 2022 | 49.126489681419 | 2021 | 49.116711732724 | 2020 | 49.13577368462 | 2019 | 49.191603255372 | 2018 | 49.248658492642 | 2017 | 49.299072709264 | 2016 | 49.344849518295 | 2015 | 49.387677036962 | 2014 | 49.428879268278 | 2013 | 49.468300063449 | 2012 | 49.505327616685 | 2011 | 49.538758735037 | 2010 | 49.593553348085 | 2009 | 49.699687833406 | 2008 | 49.837340806415 | 2007 | 49.980753301665 | 2006 | 50.127769354918 | 2005 | 50.276738505303 | 2004 | 50.426601581242 | 2003 | 50.577228164087 | 2002 | 50.728407908429 | 2001 | 50.879113955676 | 2000 | 51.015181395841 | 1999 | 51.122682074711 | 1998 | 51.217532282967 | 1997 | 51.317130201919 | 1996 | 51.421233560709 | 1995 | 51.533227299363 | 1994 | 51.654327969636 | 1993 | 51.783115445375 | 1992 | 51.919728530941 | 1991 | 52.062997613018 | 1990 | 52.213068249922 | 1989 | 52.322432599972 | 1988 | 52.386511668985 | 1987 | 52.453386770855 | 1986 | 52.523899271101 | 1985 | 52.596548299339 | 1984 | 52.67368359586 | 1983 | 52.755639665574 | 1982 | 52.841694617761 | 1981 | 52.930949287165 | 1980 | 52.899474172595 | 1979 | 52.672006610763 | 1978 | 52.369941830857 | 1977 | 52.062602091212 | 1976 | 51.749688969317 | 1975 | 51.432252073749 |
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