| Year | Value | | 2022 | 45,291 | | 2021 | 43,822 | | 2020 | 43,005 | | 2019 | 42,605 | | 2018 | 42,605 | | 2017 | 43,165 | | 2016 | 44,454 | | 2015 | 46,152 | | 2014 | 47,491 | | 2013 | 48,454 | | 2012 | 49,161 | | 2011 | 49,418 | | 2010 | 49,537 | | 2009 | 49,750 | | 2008 | 49,758 | | 2007 | 49,740 | | 2006 | 49,960 | | 2005 | 49,887 | | 2004 | 49,881 | | 2003 | 50,266 | | 2002 | 50,306 | | 2001 | 49,748 | | 2000 | 48,190 | | 1999 | 44,860 | | 1998 | 41,526 | | 1997 | 40,050 | | 1996 | 40,723 | | 1995 | 43,001 | | 1994 | 46,170 | | 1993 | 50,064 | | 1992 | 53,684 | | 1991 | 54,938 | | 1990 | 54,572 | | 1989 | 53,729 | | 1988 | 52,203 | | 1987 | 51,255 | | 1986 | 51,072 | | 1985 | 51,692 | | 1984 | 52,955 | | 1983 | 54,543 | | 1982 | 55,351 | | 1981 | 55,349 | | 1980 | 55,169 | | 1979 | 54,790 | | 1978 | 54,246 | | 1977 | 53,467 | | 1976 | 52,230 | | 1975 | 49,792 | | 1974 | 46,415 | | 1973 | 42,993 | | 1972 | 39,133 | | 1971 | 35,437 | | 1970 | 33,938 | | 1969 | 34,915 | | 1968 | 36,743 | | 1967 | 39,503 | | 1966 | 42,803 | | 1965 | 45,063 | | 1964 | 45,956 | | 1963 | 45,817 | | 1962 | 45,362 | | 1961 | 44,998 | | 1960 | 44,414 |
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