| Year | Value | | 2022 | 12,668 | | 2021 | 12,511 | | 2020 | 12,315 | | 2019 | 12,132 | | 2018 | 11,924 | | 2017 | 11,682 | | 2016 | 11,437 | | 2015 | 11,185 | | 2014 | 10,940 | | 2013 | 10,694 | | 2012 | 10,444 | | 2011 | 10,283 | | 2010 | 10,241 | | 2009 | 10,233 | | 2008 | 10,243 | | 2007 | 10,267 | | 2006 | 10,294 | | 2005 | 10,318 | | 2004 | 10,335 | | 2003 | 10,344 | | 2002 | 10,351 | | 2001 | 10,363 | | 2000 | 10,377 | | 1999 | 10,383 | | 1998 | 10,377 | | 1997 | 10,363 | | 1996 | 10,345 | | 1995 | 10,316 | | 1994 | 10,274 | | 1993 | 10,226 | | 1992 | 10,129 | | 1991 | 9,902 | | 1990 | 9,598 | | 1989 | 9,306 | | 1988 | 9,022 | | 1987 | 8,759 | | 1986 | 8,527 | | 1985 | 8,313 | | 1984 | 8,125 | | 1983 | 7,832 | | 1982 | 7,672 | | 1981 | 7,691 | | 1980 | 7,635 | | 1979 | 7,586 | | 1978 | 7,541 | | 1977 | 7,441 | | 1976 | 7,306 | | 1975 | 7,199 | | 1974 | 7,096 | | 1973 | 6,990 | | 1972 | 6,883 | | 1971 | 6,778 | | 1970 | 6,663 | | 1969 | 6,508 | | 1968 | 6,288 | | 1967 | 6,114 | | 1966 | 6,021 | | 1965 | 5,804 | | 1964 | 5,484 | | 1963 | 5,198 | | 1962 | 4,950 | | 1961 | 4,753 | | 1960 | 4,582 |
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