| Year | Value | | 2022 | 1,437 | | 2021 | 1,335 | | 2020 | 1,254 | | 2019 | 1,189 | | 2018 | 1,137 | | 2017 | 1,096 | | 2016 | 1,068 | | 2015 | 1,058 | | 2014 | 1,065 | | 2013 | 1,075 | | 2012 | 1,087 | | 2011 | 1,100 | | 2010 | 1,110 | | 2009 | 1,092 | | 2008 | 1,054 | | 2007 | 1,025 | | 2006 | 1,003 | | 2005 | 987 | | 2004 | 975 | | 2003 | 963 | | 2002 | 943 | | 2001 | 917 | | 2000 | 885 | | 1999 | 852 | | 1998 | 828 | | 1997 | 806 | | 1996 | 786 | | 1995 | 771 | | 1994 | 758 | | 1993 | 748 | | 1992 | 739 | | 1991 | 731 | | 1990 | 722 | | 1989 | 699 | | 1988 | 665 | | 1987 | 634 | | 1986 | 603 | | 1985 | 571 | | 1984 | 542 | | 1983 | 513 | | 1982 | 483 | | 1981 | 456 | | 1980 | 430 | | 1979 | 377 | | 1978 | 319 | | 1977 | 297 | | 1976 | 284 | | 1975 | 272 | | 1974 | 259 | | 1973 | 247 | | 1972 | 236 | | 1971 | 231 | | 1970 | 233 | | 1969 | 239 | | 1968 | 243 | | 1967 | 246 | | 1966 | 251 | | 1965 | 254 | | 1964 | 258 | | 1963 | 262 | | 1962 | 267 | | 1961 | 270 | | 1960 | 274 |
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