| Year | Value | | 2024 | 438 | | 2023 | 423 | | 2022 | 405 | | 2021 | 387 | | 2020 | 369 | | 2019 | 349 | | 2018 | 331 | | 2017 | 317 | | 2016 | 302 | | 2015 | 286 | | 2014 | 268 | | 2013 | 250 | | 2012 | 233 | | 2011 | 222 | | 2010 | 213 | | 2009 | 207 | | 2008 | 200 | | 2007 | 189 | | 2006 | 180 | | 2005 | 171 | | 2004 | 165 | | 2003 | 161 | | 2002 | 157 | | 2001 | 153 | | 2000 | 149 | | 1999 | 144 | | 1998 | 139 | | 1997 | 137 | | 1996 | 136 | | 1995 | 142 | | 1994 | 152 | | 1993 | 157 | | 1992 | 161 | | 1991 | 165 | | 1990 | 164 | | 1989 | 159 | | 1988 | 158 | | 1987 | 157 | | 1986 | 151 | | 1985 | 144 | | 1984 | 136 | | 1983 | 126 | | 1982 | 119 | | 1981 | 113 | | 1980 | 107 | | 1979 | 101 | | 1978 | 97 | | 1977 | 92 | | 1976 | 90 | | 1975 | 92 |
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