| Year | Value | | 2022 | 71,857 | | 2021 | 72,216 | | 2020 | 73,517 | | 2019 | 74,683 | | 2018 | 75,414 | | 2017 | 76,333 | | 2016 | 77,242 | | 2015 | 77,447 | | 2014 | 77,489 | | 2013 | 77,586 | | 2012 | 76,981 | | 2011 | 75,940 | | 2010 | 75,533 | | 2009 | 74,920 | | 2008 | 73,771 | | 2007 | 73,110 | | 2006 | 73,224 | | 2005 | 74,849 | | 2004 | 77,918 | | 2003 | 81,431 | | 2002 | 85,251 | | 2001 | 89,454 | | 2000 | 93,527 | | 1999 | 97,082 | | 1998 | 101,201 | | 1997 | 107,199 | | 1996 | 114,589 | | 1995 | 122,280 | | 1994 | 129,765 | | 1993 | 136,288 | | 1992 | 141,143 | | 1991 | 144,544 | | 1990 | 146,634 | | 1989 | 147,792 | | 1988 | 148,070 | | 1987 | 146,085 | | 1986 | 142,197 | | 1985 | 138,382 | | 1984 | 135,215 | | 1983 | 132,251 | | 1982 | 130,299 | | 1981 | 129,652 | | 1980 | 129,419 | | 1979 | 129,527 | | 1978 | 129,840 | | 1977 | 130,747 | | 1976 | 132,611 | | 1975 | 134,993 | | 1974 | 137,196 | | 1973 | 138,900 | | 1972 | 139,596 | | 1971 | 139,078 | | 1970 | 138,130 | | 1969 | 138,038 | | 1968 | 139,084 | | 1967 | 140,915 | | 1966 | 143,743 | | 1965 | 147,055 | | 1964 | 150,041 | | 1963 | 152,305 | | 1962 | 153,347 | | 1961 | 152,347 | | 1960 | 149,945 |
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