| Year | Value | | 2022 | 37,926 | | 2021 | 37,632 | | 2020 | 37,095 | | 2019 | 36,343 | | 2018 | 35,543 | | 2017 | 34,786 | | 2016 | 34,007 | | 2015 | 33,127 | | 2014 | 32,106 | | 2013 | 30,940 | | 2012 | 29,681 | | 2011 | 28,449 | | 2010 | 27,727 | | 2009 | 27,063 | | 2008 | 26,031 | | 2007 | 25,084 | | 2006 | 24,249 | | 2005 | 23,544 | | 2004 | 22,995 | | 2003 | 22,594 | | 2002 | 22,297 | | 2001 | 22,052 | | 2000 | 21,804 | | 1999 | 21,553 | | 1998 | 21,316 | | 1997 | 21,092 | | 1996 | 20,884 | | 1995 | 20,691 | | 1994 | 20,514 | | 1993 | 20,354 | | 1992 | 20,205 | | 1991 | 20,044 | | 1990 | 19,843 | | 1989 | 19,599 | | 1988 | 19,300 | | 1987 | 18,961 | | 1986 | 18,625 | | 1985 | 18,306 | | 1984 | 17,998 | | 1983 | 17,706 | | 1982 | 17,418 | | 1981 | 17,090 | | 1980 | 16,690 | | 1979 | 16,225 | | 1978 | 15,701 | | 1977 | 15,112 | | 1976 | 14,486 | | 1975 | 13,842 | | 1974 | 13,175 | | 1973 | 12,468 | | 1972 | 11,757 | | 1971 | 11,108 | | 1970 | 10,562 | | 1969 | 10,132 | | 1968 | 9,847 | | 1967 | 9,684 | | 1966 | 9,548 | | 1965 | 9,372 | | 1964 | 9,169 | | 1963 | 8,944 | | 1962 | 8,688 | | 1961 | 8,461 | | 1960 | 8,326 |
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