| Year | Value | | 2022 | 34,341 | | 2021 | 35,520 | | 2020 | 36,510 | | 2019 | 36,887 | | 2018 | 37,017 | | 2017 | 37,291 | | 2016 | 37,751 | | 2015 | 38,450 | | 2014 | 39,425 | | 2013 | 40,709 | | 2012 | 42,349 | | 2011 | 44,411 | | 2010 | 46,968 | | 2009 | 50,106 | | 2008 | 53,949 | | 2007 | 55,880 | | 2006 | 54,767 | | 2005 | 52,609 | | 2004 | 49,943 | | 2003 | 47,008 | | 2002 | 44,024 | | 2001 | 40,986 | | 2000 | 37,546 | | 1999 | 32,821 | | 1998 | 29,405 | | 1997 | 27,436 | | 1996 | 24,347 | | 1995 | 20,762 | | 1994 | 19,559 | | 1993 | 20,977 | | 1992 | 22,362 | | 1991 | 24,022 | | 1990 | 26,345 | | 1989 | 29,251 | | 1988 | 32,883 | | 1987 | 29,041 | | 1986 | 22,810 | | 1985 | 21,716 | | 1984 | 20,134 | | 1983 | 18,386 | | 1982 | 16,482 | | 1981 | 14,454 | | 1980 | 12,348 | | 1979 | 10,131 | | 1978 | 7,933 | | 1977 | 6,757 | | 1976 | 6,528 | | 1975 | 6,322 | | 1974 | 6,116 | | 1973 | 5,913 | | 1972 | 5,716 | | 1971 | 5,529 | | 1970 | 5,352 | | 1969 | 5,188 | | 1968 | 5,028 | | 1967 | 4,867 | | 1966 | 4,709 | | 1965 | 4,557 | | 1964 | 4,416 | | 1963 | 4,280 | | 1962 | 4,148 | | 1961 | 4,024 | | 1960 | 3,904 |
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