| Year | Value | | 2022 | 17,143 | | 2021 | 16,883 | | 2020 | 16,768 | | 2019 | 16,615 | | 2018 | 16,572 | | 2017 | 16,545 | | 2016 | 16,428 | | 2015 | 15,777 | | 2014 | 14,987 | | 2013 | 14,184 | | 2012 | 13,221 | | 2011 | 12,462 | | 2010 | 11,868 | | 2009 | 11,168 | | 2008 | 10,373 | | 2007 | 9,618 | | 2006 | 9,028 | | 2005 | 8,623 | | 2004 | 8,344 | | 2003 | 8,276 | | 2002 | 8,352 | | 2001 | 8,366 | | 2000 | 8,330 | | 1999 | 8,250 | | 1998 | 8,150 | | 1997 | 8,048 | | 1996 | 7,923 | | 1995 | 7,760 | | 1994 | 7,552 | | 1993 | 7,252 | | 1992 | 6,889 | | 1991 | 6,546 | | 1990 | 6,235 | | 1989 | 5,965 | | 1988 | 5,734 | | 1987 | 5,533 | | 1986 | 5,353 | | 1985 | 5,174 | | 1984 | 4,991 | | 1983 | 4,806 | | 1982 | 4,630 | | 1981 | 4,466 | | 1980 | 4,316 | | 1979 | 4,172 | | 1978 | 4,032 | | 1977 | 3,902 | | 1976 | 3,779 | | 1975 | 3,669 | | 1974 | 3,575 | | 1973 | 3,501 | | 1972 | 3,442 | | 1971 | 3,379 | | 1970 | 3,305 | | 1969 | 3,224 | | 1968 | 3,135 | | 1967 | 3,038 | | 1966 | 2,946 | | 1965 | 2,865 | | 1964 | 2,794 | | 1963 | 2,734 | | 1962 | 2,685 | | 1961 | 2,641 | | 1960 | 2,597 |
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