| Year | Value | | 2022 | 5,016 | | 2021 | 4,780 | | 2020 | 4,595 | | 2019 | 4,391 | | 2018 | 4,173 | | 2017 | 4,080 | | 2016 | 4,096 | | 2015 | 4,120 | | 2014 | 4,132 | | 2013 | 4,126 | | 2012 | 4,094 | | 2011 | 4,027 | | 2010 | 3,970 | | 2009 | 3,981 | | 2008 | 4,026 | | 2007 | 4,035 | | 2006 | 4,044 | | 2005 | 4,028 | | 2004 | 3,931 | | 2003 | 3,821 | | 2002 | 3,723 | | 2001 | 3,623 | | 2000 | 3,567 | | 1999 | 3,606 | | 1998 | 3,711 | | 1997 | 3,824 | | 1996 | 3,931 | | 1995 | 4,002 | | 1994 | 4,009 | | 1993 | 3,965 | | 1992 | 3,897 | | 1991 | 3,830 | | 1990 | 3,796 | | 1989 | 3,781 | | 1988 | 3,744 | | 1987 | 3,672 | | 1986 | 3,574 | | 1985 | 3,481 | | 1984 | 3,414 | | 1983 | 3,398 | | 1982 | 3,426 | | 1981 | 3,432 | | 1980 | 3,365 | | 1979 | 3,243 | | 1978 | 3,077 | | 1977 | 2,859 | | 1976 | 2,644 | | 1975 | 2,471 | | 1974 | 2,333 | | 1973 | 2,221 | | 1972 | 2,141 | | 1971 | 2,085 | | 1970 | 2,056 | | 1969 | 2,057 | | 1968 | 2,097 | | 1967 | 2,167 | | 1966 | 2,221 | | 1965 | 2,231 | | 1964 | 2,196 | | 1963 | 2,108 | | 1962 | 1,974 | | 1961 | 1,839 | | 1960 | 1,736 |
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