| Year | Value | | 2022 | 8,877 | | 2021 | 9,036 | | 2020 | 9,232 | | 2019 | 9,393 | | 2018 | 9,442 | | 2017 | 9,344 | | 2016 | 9,184 | | 2015 | 9,093 | | 2014 | 9,104 | | 2013 | 9,239 | | 2012 | 9,439 | | 2011 | 9,517 | | 2010 | 9,448 | | 2009 | 9,360 | | 2008 | 9,268 | | 2007 | 9,165 | | 2006 | 9,177 | | 2005 | 9,322 | | 2004 | 9,505 | | 2003 | 9,701 | | 2002 | 9,981 | | 2001 | 10,290 | | 2000 | 10,528 | | 1999 | 10,672 | | 1998 | 10,739 | | 1997 | 10,786 | | 1996 | 10,844 | | 1995 | 10,967 | | 1994 | 11,185 | | 1993 | 11,440 | | 1992 | 11,679 | | 1991 | 11,891 | | 1990 | 12,080 | | 1989 | 12,293 | | 1988 | 12,504 | | 1987 | 12,630 | | 1986 | 12,661 | | 1985 | 12,600 | | 1984 | 12,449 | | 1983 | 12,217 | | 1982 | 11,914 | | 1981 | 11,557 | | 1980 | 11,165 | | 1979 | 10,674 | | 1978 | 10,154 | | 1977 | 9,681 | | 1976 | 9,180 | | 1975 | 8,646 | | 1974 | 8,162 | | 1973 | 7,682 | | 1972 | 7,151 | | 1971 | 6,666 | | 1970 | 6,266 | | 1969 | 5,972 | | 1968 | 5,793 | | 1967 | 5,765 | | 1966 | 5,889 | | 1965 | 6,124 | | 1964 | 6,454 | | 1963 | 6,860 | | 1962 | 7,257 | | 1961 | 7,573 | | 1960 | 7,724 |
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