| Year | Value | | 2022 | 2,298 | | 2021 | 2,224 | | 2020 | 2,141 | | 2019 | 2,040 | | 2018 | 1,918 | | 2017 | 1,809 | | 2016 | 1,745 | | 2015 | 1,697 | | 2014 | 1,633 | | 2013 | 1,562 | | 2012 | 1,486 | | 2011 | 1,388 | | 2010 | 1,288 | | 2009 | 1,214 | | 2008 | 1,157 | | 2007 | 1,102 | | 2006 | 1,039 | | 2005 | 979 | | 2004 | 928 | | 2003 | 886 | | 2002 | 859 | | 2001 | 845 | | 2000 | 836 | | 1999 | 832 | | 1998 | 832 | | 1997 | 824 | | 1996 | 806 | | 1995 | 795 | | 1994 | 793 | | 1993 | 796 | | 1992 | 802 | | 1991 | 805 | | 1990 | 827 | | 1989 | 874 | | 1988 | 935 | | 1987 | 1,009 | | 1986 | 1,084 | | 1985 | 1,152 | | 1984 | 1,207 | | 1983 | 1,223 | | 1982 | 1,207 | | 1981 | 1,187 | | 1980 | 1,167 | | 1979 | 1,153 | | 1978 | 1,145 | | 1977 | 1,138 | | 1976 | 1,127 | | 1975 | 1,109 | | 1974 | 1,086 | | 1973 | 1,053 | | 1972 | 1,009 | | 1971 | 957 | | 1970 | 898 | | 1969 | 843 | | 1968 | 805 | | 1967 | 791 | | 1966 | 796 | | 1965 | 812 | | 1964 | 828 | | 1963 | 811 | | 1962 | 764 | | 1961 | 712 | | 1960 | 657 |
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